Chrysler 300M and LHS Body Systems

Based on information provided by Chrysler Corporation. Edited for readability.

Click here for a summary of changes from the last generation

Click here for a review of the 2000 and 2001 Chrysler 300M.

Chrysler 300M production"Mr. Source" noted the 300M changes for 2003: "No more chrome exhaust tips. The chrome rims are the same used on the 02 Concorde Limited ( the Concorde and300M now share this rim) . Digital radio. 6 disc cd changer replaces the 4 disc unit. There were more but they were things like wire connections changed etc. Things you would never notice."

Changes from the prior generation

Torsional stiffness was 37% greater and bending stiffness 46% greater than the prior bodies, which were best in class when introduced. Structural stiffness provided a solid feeling and helped make handling precise by allowing the suspension to respond to cornering loads without deflecting the body.

The new body structures also attenuated noise through localized stiffening. These were the first body structures developed by Chrysler using both objective testing and computer analysis. The analysis and optimization process tuned the stiffness of structural paths from external noise sources, such as the engine and suspension system, to the passenger compartment, preventing the noise from being audible. Structural refinement was especially important because a large portion of structureborne noise occurs at frequencies below 400 Hertz (cycles per second), which was difficult to block.

The following features contributed to structural stiffness:

  • At the forward front suspension cradle attachments and at all four rear suspension cross member attachments, the body structure included doubleshear mounts. Mounting bolts for these components attached to body structural beams through surface mounting holes and sleeves welded inside the beams. The sleeves stiffened the beams at the attachment point, suppressing inputs to the passenger compartment
  • A tubular cross beam bolted to the cowl sides beneath the instrument panel increased body torsional rigidity and enhanced steering column stiffness. The beam was straight to provide maximum contribution to stiffness with a minimum of added weight. This beam also enhanced instrument panel stability
  • A boltin structural beam connecting the tops of the front suspension strut towers and stiffening of the tower structures enhanced torsional stiffness of the body structure
  • To increase torsional stiffness at the rear of the structure, a transverse beam was welded to the top of the rear strut towers. This compact beam fit neatly under the shelf panel, leaving a large passthough area for use with folding rear seats. These beams also contributed to noise attenuation and reduced the potential for BSRs (buzzes, squeaks and rattles)
  • High overall bending stiffness also reduced the potential for BSRs from secondary components such as the instrument panel and steering column, because the structure did not transmit their natural frequencies
  • Structural sill construction, having no styled surface, contributed to a stiffer structure by allowing more overlap between center pillar and sill than was possible when the sill structure was also the styled surface
  • Laserwelded, front longitudinal rails with differential thickness sections provided needed stiffness more efficiently than single thickness parts with added reinforcements
  • Stiffer suspension attachment points
  • Stiffer front strut towers included a cap reinforcement
  • Threepiece rear strut tower and wheelhouse assemblies reduced deflection; lowcontour areas included stamped beads to increase local stiffness
  • An extensive system of beads stamped into all lowcontour floor pan areas increased local stiffness

Body Panel Accuracy

Chrysler LHS and 300M had a "two millimeter" body, meaning that all measured characteristics are maintained within 2 mm of the designed position.

Shell Construction

Onepiece bodyside aperture panels formed the door openings, providing excellent dimensional control and high quality fit and finish. Controlling door opening dimensions also helped ensure good door sealing. Furthermore onepiece bodyside aperture construction enhanced body stiffness by reducing the number of parts and welding joints required. The number of major stampings in the body side was reduced from 15 to 10.

Throughout the body, part consolidation reduced the number of stampings. A typical example was the quarter inner panel construction where one stamping replaced three on the prior body. In another area, the center pillar overlapped the sill, eliminating three additional stampings previously used. Dimensional accuracy was enhanced by reducing the number of pieces because additive tolerances associated with multiple parts and their respective welding operations do not exist.

Weight Reduction

Chrysler LHS and 300M used lightweight materials and an optimized structure to reduce weight. Extensive use of highstrength steel for the front and rear longitudinal rails, center pillars and other areas affected by impact requirements reduced body shell weight by an estimated 40 pounds (18 kg).


An aluminum hood on LHS reduced weight by 20 pounds (9 kg) compared to an equivalent part in steel. This feature was recently introduced on Concorde as Chrysler's first highvolume aluminum exterior body panel. The 300M steel hood was also lightened by optimizing the inner panel structure.

All hoods had singlepivot rear hinges, which were adjustable for accurate hood fit and gas prop counterbalance supports. On LHS, the gas prop pivot points on the hood were closer to the front to reduce deflection in the more flexible aluminum material.

Latches were placed at the leading edges of the hoods to permit the hoods to fit closely around the head lamps without the possibility of contact if the hood was slammed shut. The secondary release mechanism was readily accessible and had a yellow handle for easy identification.

Trunk Lid And Mechanism

New four bar trunk lid hinges with gas prop counterbalancing increased usable trunk volume and improved trunk lid to body fit. Computer designed hinge and prop geometry made opening the lid easy. Lifting the lid a nominal amount brought the counterbalance forces into effect. Reaching the full open position from there required little or no effort. The hinges and props mounted completely outside the trunk opening to avoid intruding on luggage capacity when closed a major improvement over prior models. The four bar linkage two pivoting links on each side of the trunk opening connecting the lid to the body was more compact than the former goose neck hinges, while providing ample room for loading. This hinge system was also strong and stable, providing lonterm alignment accuracy and durability.

The trunk was sealed by a full perimeter tubular weatherstrip attached to a raised flange surrounding the opening. The raised flange prevented water from running into the opening when the lid was open.

FullCoverage Wheelhouse Liners

Full coverage, molded plastic front and rear wheelhouse liners protected the body structure from potentially corrosive road splash and prevented noise due to stone impingement on the body shell.

Exterior Ornamentation

Highimpact, molded plastic sill cladding, which was painted body color, resisted chipping and did not rust if chipped.

One piece, diecast zinc side window opening moldings had better dimensional control than multipiece stampings for outstanding fit and finish. One piece construction provided a smooth appearance free of joint lines, and ensured consistent gloss and color. Moldings were flush with the outer surfaces of the doors and formed the outer half of the glass channel, allowing the glass to more closely approach the surrounding sheet metal for a smooth, aerodynamic appearance and reduced wind noise. Using diecast zinc, which was stronger than aluminum, provided the shallowest possible moldings and a highquality surface finish. The moldings had a black, powdercoat paint finish. To prevent wind and other noises, a polyethylene foam backing was placed between the moldings and the door outer panels. "Flags" incorporated into each rear door molding aft of the window provided a smoothly curved continuation of the window opening.

Bodyside moldings provided effective protection against parking lot damage. New injection molded construction provided preformed ends for a neat appearance. Inert gas injection in the molding process provided a uniform outer surface and thinwall construction that reduced weight compared to solidly molded parts.


Solar Control Glass in all windows reduced the transmission of infrared and ultraviolet energy to minimize interior heating and damage to organic materials from solar radiation.

A rear window molding injectionmolded onto the glass was seamfree to provide a close fit to the body opening and a neat appearance. The molding included mounting clips and positioning spacers to ensure easier assembly and accurate alignment of the window on the body.

Bumpers, Fascias And Grilles

Front and rear bumper and fascia systems fitted close to adjacent body panels while providing impact protection for safety related equipment at speeds up to 2.5 mph (4 km/hr). The bumper systems also met the Canadian regulation for protection up to 5 mph (8 km/hr). Fascias were molded of either TPO (thermoplastic olefin) or RRIM (reactioninjection molded urethane). Both materials were reformulated to increase abrasion resistance relative to their predecessors.

Beams, shorter than in past practices, terminated in lightweight, high-impact molded plastic inserts. These inserts also contributed to highspeed barrier impact energy management by extending the load path from the longitudinal rails of the body structure to the front of the bumper face bar. A patent was pending on this aspect of the bumper system.

High-impact plastic grilles resisted damage in low speed impacts. Lightweight fascia modules were constructed of RRIM.

Exterior Lighting

Head Lamps

New halogenbulb, quad head lamps provided a broader and longer beam pattern on the road than their predecessors. In highbeam mode, all four units were lit to maximize light output. The new highbeam units produced double the light output of their predecessors and reached 65% farther down the road. Low beams produced 50% more light. Each produced a brightly illuminated field of view with an evenly blended light pattern. On all car lines, light was focused solely by computerdesigned reflectors. Using the same bulbs as their predecessors, these reflectors were twice as efficient at projecting light down the road. Aiming was done by moving the reflector within the lamp assembly. Each lamp included a bubble level and readily accessible adjustment screws for reaiming the head lamps, if necessary.

300M models sold in Europe used projector lowbeam bulbs that included lens masks to limit upward light distribution and unique halogen highbeam bulbs.

Fog Lamps

New, more powerful fog lamps were integrated with the front fascias on Chrysler LHS and 300M. To increase their effectiveness as fog lamps, new switch logic allowed them to operate with parking lamps, but without head lamps. They also continued to operate as a supplement to the head lamps if desired, but turned off automatically when highbeam head lamps were selected (as in the past). Rear fog lamps in the 300M were standard in Europe.

Head Lamp Washers

In Europe, 300M included head lamp washers. Each washer unit had two discrete nozzles to direct fluid onto the head lamp lens. The units were spring loaded and automatically retracted after use.

Door Systems

Full-stamped door construction inner and outer panels both encompassing the windows was simpler and dimensionally more accurate than the prior construction method, improving door fit. Reducing the number of parts allowed a corresponding reduction in welding operations and the potential for variations resulting from each operation. Door inner panels were stamped from dual thickness, laser-welded sheet metal to increase accuracy of the doors. Laserwelded inner panels eliminated the need for a separate welded-in reinforcement, the single largest cause of variation in door assembly. Instead of adding a reinforcement, the forward portion of the panel, to which the hinges were bolted, was nearly three times as thick as the remainder of the panel. The added thickness provided hinge mounting stability and contributed to a solid door closing sound. Furthermore, this inner panel construction was also lighter than a single-thickness panel with a welded reinforcement. To form the inner panel, sheets of dissimilar thickness steel were butted together and welded by a laser beam. The resulting weld joint was smooth and unobtrusive. Locating points in the inner panel stamping presses ensured that the weld seam was accurately aligned for proper sealing of the door in the door opening. One piece aperture panels in the body sides facing the doors contributed to consistency of door fit.

Door Hinges and Latches

Door hinge design and mounting provided more accurate door placement than the prior configuration. Hinge inner and outer halves were permanently assembled, reducing clearance required by the prior replaceable pivot pin system. Hinge attachment to the doors and pillars was controlled by alignment fixtures, eliminating the need for manual adjustment and its potential errors.

New door latches provided smoother and quieter operation. The new design provided 100% isolation against metal to metal contact between the latch pawl and the striker for quietness. New power lock motors were now virtually inaudible.

New door ajar switches were integral with the door latch assemblies and operated both courtesy lamps and the door ajar indicator in the instrument cluster. This construction was more reliable and durable than previous standalone switches less susceptible to door adjustments, freezing, contamination and corrosion.

Weather Stripping

A body-mounted tubular weather strip encircled each door opening to provide primary sealing against wind noise and water leaks. A second body-mounted weather strip running up the windshield pillar and across the tops of the doors incorporated a trough to channel water away from the door opening. This sealing system prevented rain water from running into the passenger compartment when the doors were opened. A tubular-type weather strip attached to the leading edge of each rear door above the belt line prevented wind noise and acted as a sight shield. A tubular weather strip attached to the back of each door between the sill and the belt line also handled wind noise. Lip-type weather strips attached to the sill cladding sealed the gap between doors and sills to keep road splash and dust out of the door openings and blocked wind and road noise more effectively than door-mounted weather strips. These weather strips snapped into the sill cladding and also covered the cladding attachments.

Door Glass

Front door glass was cylindrical for fit and finish accuracy and easy window operation. Rear door glass was barrel shaped to conform to the compound curvature of the doors. As in the past, the rear windows lowered only partially, to permit wider door openings.

Rearview Mirrors

Dual, heated power outside mirrors with position memory were standard in the U.S. and Europe. The mirrors folded in (except US 300M). An automatic dimming daynight mirror inside mirror was standard. It had true grayscale light absorption, becoming progressively darker as the intensity of incoming light increases and returning automatically to normal levels when intensity decreases.

Power Moonroof

An optional vent-and-slide power moonroof used Solar Cool Gray® reflective glass to block out ultraviolet light and up to 81% of visible light, minimizing interior heating and damage to organic materials from solar radiation. The unit was thin at least 0.25 in. (6 mm) thinner than competitive units to minimize passenger compartment intrusion. An opening 33.2 in. (844 mm) wide provided the driver and front passenger with clear views. An "express" open feature in the open mode caused the panel to move immediately to the full open position when the OPEN rocker switch was pressed. Pressing the switch again before the panel reaches the full open position stopped movement. An electronic control system used Halleffect sensors rather than mechanical switches at the limits of panel movement.

The interior roof panel and headliner conformed to the moonroof opening for a finished appearance without an add-on welt or molding. A laminated plastic sunshade was covered with foambacked headliner fabric. It opened manually using a recessed handle molded into the surface or slid back automatically when the moonroof opened.

To minimize wind noise and buffeting, a curved air deflector popped up at the front of the roof opening and the panel stopped short of the full open position. The height of the air deflector and the open position stopping point were optimized in proving grounds tests. Positive sealing was ensured by a cam system that moved the panel into the closed position from the top down. A compact electric motor at the rear of the structure moved the panel with cables that were enclosed for smooth and quiet operation. Tempered glass protected the occupants from injury in the event of breakage. When broken, it crumbled into small pieces without sharp edges. Urethane encapsulation of the glass provided a neat installation.

Windshield Wiper & Washer System

Computer modeling of the wiper linkage determined appropriate wiper pivot locations and helped determine the windshield configuration required to maintain appropriate blade pressure. Aerodynamic design of the hood and cowl screen smoothed air flow, helping to hold the wiper blades on the glass at the vehicles' highest attainable speeds without air foils. This air flow pattern also caused water pushed down by the wipers to flow to the sides rather than running back up the glass. Aerodynamic design of the windshield pillar shape and molding guides water swept aside by the wipers upward, keeping the lower portions of the side windows clear. Coldweather wiper performance was enhanced by a new defroster system that effectively cleared frost from the glass and melts snow pushed down the base of the windshield by the wipers. New wiper control logic returned the blades to their parked position when the ignition was turned off, if the wipers were operating at that time. The intermittent wipe delay time was doubled when the car was moving less than 10 mph (16 km/hr). New wiper blades were three times as strong as current blades. Bolton wiper arms were simpler to manufacture and more robust than the "latchlock" arms used previously.

A 30 psi (207 kPa) high output pump supplied two hood-mounted washer nozzle assemblies. Each nozzle assembly had three jets providing a triangular spray pattern that effectively covered the wiped area of the windshield. The spray nozzle design, pattern and pump pressure requirement were developed through extensive aerodynamic testing. A new washer fluid level sensor in the 110ounce (3.25liter) reservoir provided a more accurate indication of low fluid.



A driver's power seat memory feature, part of the Personalized Memory System, was available on LHS. It allowed two drivers to preselect the combination of cushion height and angle, back angle and track position. They preferred using the remote keyless entry (RKE) key fob transmitter or memory switches housed in a pod on the front outboard corner of the seat cushion side shield.

The memory seat also included a GlideToExit feature offered here for the first time on a Chrysler vehicle. GlideToExit made driver entry and exit easier by sliding the seat rearward up to 2.2 inches (55 mm) from the preselected position, if track travel allowed it. GlideToExit provided the following actions:

The seat moved rearward when the key was removed from the ignition, or when a memory seat switch or an RKE key fob unlock button was pressed prior to entering the vehicle. The seat returned to the preselected position, when the driver pulled the seat belt out prior to buckling or when the ignition was switched on after entry, whichever came first.

Heated driver and front passenger seats on LHS had two temperature settings.

Standard fourway adjustable front head restraints added flexibility and comfort. In addition to vertical adjustment, each head restraint provided 1.6 inches (40 mm) of fore and aft adjustment by pivoting about a transverse, horizontal axis.

A rear seat pass through feature combined an opening to the trunk with a folding center armrest. The 8.6 x 8.0inch (220 x 205 mm) opening comfortably allowed two pairs of skis or other long objects to extend from the trunk into the passenger compartment. The pass through, which was concealed when the armrest was upright, had a separate hinged cover with a springloaded latch. Pressing the recessed latch lever at the top and pulling forward opened the cover down on the armrest. The back of the cover was trimmed with needled fiber carpeting that matched the trunk trim. An optional bag to protect the car's interior, which was available from a dealer, clamps to a flange on the opening.

The armrest also included a pull strap and a covered storage compartment with a latching lid. Each cavity of the dual cup holder at the front of the armrest held a coffee mug with handle or a soft drink cup up to 48 ounces (1.4liters).

The rear seat also included head rests integral with the back at the outboard seating positions.


300M had the same front seat power, memory, heat and head restraint features as LHS.

A folding 60/40 splitback seat with center armrest gave storage versatility. The armrest was integral with the 60% portion of the seat. A pull strap facilitated opening the armrest separately. The rear panel of the seat back covered the area behind the armrest when the armrest was folded. The opening to the trunk was wider and taller than that provided by competitive cars because the supporting structure nestled beneath the shelf panel. When both sections were folded, the opening was over 15 x 47 inches (400 x 1200 mm). A positive latch recessed in each back section held it in the upright position. High on each back, a strap to operate the latch extended forward through the gap between the back and the fixed bolster between back and body structure. The latches could only be operated from the inside of the car and the straps could be tucked into the gap for improved appearance and security. A one-piece bolster at the top and sides of the seat concealed structural support for the folding sections.

New to Chrysler were vertically adjustable head restraints, which provided added comfort for outboard rear passengers. Total adjustment was 1.5 inches (60 mm) with a detent at the midpoint. Adjustment detents were springloaded.

Shared Seating Features

Seats were designed first to fit driving needs. Firm, full foam seat pads provided long-term comfort. A layer of supersoft foam placed over the pads enhanced comfort and durability. Cover seams were placed in low pressure areas to enhance comfort.

New cushion wings were lower in front, allowing occupants to sit comfortably in a splayed position. Backs were taller and wider for added shoulder support. They also offered deeper wings for lateral support. Upper backs have added contour for lateral shoulder support. Frames and pads were developed simultaneously to assure proper support. Stamped aluminum front seat pans reduced weight while providing the same aid in controlling occupant movement in a frontal impact as their steel predecessors. Deep rear seat cushions provided comfortable support for both adults and children.

  • Front seat backs were 1 in. (25 mm) taller than previous generation platform vehicles for added comfort and a richer, more substantial appearance
  • Front head restraints were larger and farther forward for added comfort when used as head rests and for added protection
  • The highest position of the front head restraints was raised 0.87 in. (22 mm) compared to previous generation platform vehicles for added occupant protection
  • Front head restraints incorporated a push button latch to secure them at the intended height.
    The springloaded push button was incorporated into the bezel at the base of the left post of each twin post head restraint. For convenience, they may be raised by simply lifting upward. Operation of the pushbutton latch was required only for downward movement. Internal stops on the posts prevented removal of the head restraints
  • A passenger front seatback map pocket was standard
  • Power seat systems included sixway cushion adjustment and power recliners operated by an ergonomic power seat switch. Movement of the seat corresponded with movement of the ergonomic switch knobs, which are shaped and positioned like a seat cushion and back. Compared to previous generation platform vehicles, vertical adjustment provided 0.15inch (4mm) of additional downward adjustment below the design position to better accommodate large drivers. Total vertical travel at the front and rear of the cushion remained 1.75 inches (44 mm). Longitudinal travel remained 8.7 inches (220 mm)
  • The driver's seat included a four position, manual lumbar support operated by a lever on the outboard side of the seat back
  • Front seat recliners provided 50° of angular adjustment

Instrument Clusters

Chrysler LHS and 300M instrument clusters provided the following features:

  • Four analog gauges speedometer, tachometer, fuel level and engine coolant temperature were controlled by a microprocessor in the cluster that smoothed and damped pointer movement to give informative and aesthetically pleasing readings
  • A not quite accurate but closer than before fuel gauge matching US customer expectations:
    • When the tank was full the gauge always "pegged" on the full mark
    • The pointer did not begin to drop immediately after a fillup
    • At least half the fuel in the tank would be consumed at the midpoint on the gauge
    • The low fuel lamp came on with less than 2.5 gallons (9.5liters) in the tank. The empty mark was reached with approximately 1.01.5 gallons (3.85.5liters) remaining in the tank
    • An arrow in the fuel gauge adjacent to the fuel pump icon pointed to the left, indicating the filler door location
  • A push button toggled between the total and trip odometer displays. Pressing and holding the button while in the trip mode reset the trip odometer. When the ignition was turned on, the display showed the function cumulative or trip that was displayed when the ignition was turned off. The display illuminated briefly when any door was opened, aiding service personnel and others wishing to check the odometer reading with the ignition off
  • All warning and information indicators (a total of 18), many of which included a chime warning, were located in the cluster for easy visibility. Nomenclature and graphics were visible only when illuminated. Allowing the gauge graphics to appear while masking the indicators was achieved through a multilayer screen printing process. Red and amber indicators used LEDs, which were designed to last the life of the vehicle.
  • White gauge faces contrasted with opaque black graphics and pointers. Red graphics were used sparingly for emphasis: maximum engine speed, fuel tank empty and coolant temperature hot. Electroluminescent lighting was uniform, compact and easily colored to match other displays, while requiring very little power. The lighting produced very little heat and lasted the life of the car with no bulbs to replace.

Both Chrysler LHS and 300M featured an electronic analog clock in the instrument panel above the central bank of air outlets.

Instrument Panel

The instrument panel structure was stiffer to control NVH, lighter to aid vehicle fuel economy and less costly to manufacture than its predecessor. It provided the following features:

  • A composite structure of steel and molded plastic provides strength and impact resistance with light weight. A complex combination of brackets, ribbing and struts supports the panel, which attaches to the cowl sides, the floor pan tunnel and the fence area just below the windshield
  • An industry first soft touch TPU (thermoplastic urethane) outer surface of the upper panel was integrally molded over urethane foam padding and a Noryl® structural retainer
  • Visible cut lines on the instrument panel surface were minimized through part consolidation to provide a more finished appearance
  • Outboard air outlets and side window demister grilles were moved from the door trim panels to the instrument panels, improving air flow performance, reducing weight and enhancing customer value by avoiding unnecessary complexity
  • An invisible seam passenger air bag door was integral with the instrument panel face as on Concorde, which was the first at Chrysler to use this feature in a "top mount" location. (Chrysler minivan invisible seam passenger air bag doors were located in the cooler face area of the panel.) This new air bag door provided the following customer benefits:
    • Reduced potential for passenger air bag theft
    • Reduced potential for tampering with passenger air bag
    • Comparable repair cost to an instrument panel having a separate air bag door, because most collisions of sufficient intensity to trigger the air bag usually also caused considerable damage to the panel structure, necessitating replacement
  • A bin type glove compartment had the same configuration but more room than the previous one.

Center Console

The center console used in both Chrysler LHS and 300M was integrated with the instrument panel. The console provided the following new features:

  • The foam padded vinyl armrest provided increased comfort. The concave armrest surface provided a wide area that cradled one's elbow and permitted both driver and passenger to use the armrest simultaneously
  • A dual element cup holder was concealed in the front face of the console. Pressing on the concealing panel released a latch and the unit swung into place automatically. Deep cup depressions had flexible tabs that adapted to and retained a wider range of commonly used containers. This included a console cup holder for up to a 20-ounce (0.6-liter) bottle, a coffee mug with handle, a 24-ounce (0.7-liter) fast food drink cup or a large box of french fries
  • Spring-loaded hinges on the side of the console lid facilitated access to the storage bin. It made the lid easy to open and held the lid open during access.
  • Tissue pack storage and a pen holder were molded into the underside of the lid
  • Two cylindrical coin holders were molded into the front face of the storage bin. One cylinder held U.S. quarters and nickels, the other nickels and dimes. The side of each cylinder facing the storage bin was cut away, leaving the edges of the coins accessible for easy removal. The bottom of each cylinder sloped toward the cutaway side to make the smaller coins accessible
  • Slots in the base of the bin stored CD boxes and/or cassettes
  • The console included lighting for the automatic transmission shift indicator nomenclature.
    This indicator provided a reference for gear selection day or night. As in the past, the instrument cluster showed exactly which gear was selected
  • A multi-element sliding cover "fish scales" concealed the slot in which the shifter moves for a neat appearance
  • An ash receiver/storage tray and power outlet/lighter were concealed, when not in use, by a hinged cover. The outlet was standard and included a labeled, snap-in cover. The ash container had a raised tab to make removal easy. The ash receiver was illuminated when exterior lamps were on through a window in the rear of the container, making night-time use easier

Steering Column and Shifter

A new, fourspoke steering wheel afforded a greater variety of comfortable hand positions than the previous wheel's two thick spokes. Upper spokes were positioned to facilitate visibility of instruments and the multi-function switch. A new tilt steering column provided an additional position. The additional position increased travel by approximately 5 degrees. Lightweight components, in conjunction with rigid mounting to the boltin crosscar beam, provided greater steering column stiffness than that of its predecessor, minimizing steering wheel shake and vibration.

Steering system weight reductions and their related benefits were as follows:

  • Use of magnesium for the steering column casting saved 2.3 lb. (1 kg). The magnesium casting replaced five parts and provided solid attachments to the body structure for increased column stability and more precise assembly for improved quality
  • The steering wheel armature was also magnesium, saving 2.4 lb. (1.1 kg). The magnesium armature damped vibration, provided deflection characteristics that contributed to driver impact protection, and was light to enhance steering responsiveness
  • Aluminum components in the intermediate steering shaft assembly saved 0.8 lb. (0.4 kg). Intermediate shaft aluminum components also provided improved performance

The shifter featured an ergonomic "cobrahead" knob with frontmounted gaterelease button, used previously only with AutoStick®. The reference shift indicator in the console illuminates when exterior lamps were on.

Speed Control System

New momentary contact push button speed control (cruise control) switches returned to their static position when released. Switches had a positive snap action with solid tactile feedback. A new switch arrangement used the corporate consensus architecture:

  • ON/OFF and SET buttons on the left initiate and terminate action
  • ACCEL/RESUME, CANCEL and COAST push buttons on the right allowed one hand control of the system while the vehicle is in motion

A "tapdown" feature operated by the COAST button reduced the set speed 2 mph (3 km/hr) each time the button was pressed momentarily. The CANCEL button, which was between the rockers, disengaged the speed control, but retained the previous set speed in memory where it could be reestablished by pressing RESUME. Pressing CANCEL, which was new to these car lines, had the same effect as tapping the brake pedal. A green CRUISE indicator in the instrument cluster illuminated when the system was on.

Horn Switch

The horn switch was concealed beneath the upper portion of the flexible steering wheel trim pad, the place customers say was the most natural for them to use. The switch consisted of two flexible, closely spaced membrane contacts attached to the underside of the trim cover. It was actuated by pressing on the large 2.1 x 5.7 inch (53 x 145 mm) slightly raised area of the cover to bring the contacts together.

Instrument PanelMounted Controls

Control logic of the new, illuminated, low current, resistive multi-plexed head lamp switch allowed the fog lamps to operate with either parking lamps or low beam head lamps. LHS was also equipped with automatic head lamps. A new feature turned the lights on when windshield wipers were used .

A new, low current, resistive multi-plexed dimmer switch retained the thumb wheel method of operation and location on the instrument panel to the right of the head lamp switch. Switch graphics were lighted when exterior lamps were on. This switch provided the following functions:

  • Courtesy lamp operation by rotating the thumb wheel upward to the full travel position (Second detent past the fulldim position)
  • Variable instrument panel, cluster display and console shift indicator brightness when exterior lamps are on at night
  • Daytime instrument cluster display brightness when exterior lamps were turned on during daylight
    (First detent past the full dim position)

A new trunk lid release push button mounted on the instrument panel to the left of the steering column where it was clearly visible and easy to reach. New control logic in the BCM disabled the release mechanism when the transmission was not in 'Park' or, on cars with the Vehicle Theft Alarm, when the alarm was armed.

A manual emergency brake release handle replaced the previous pedal operated mechanism.

HVAC System

The new Automatic Temperature Control (ATC) system showed the selected temperature at all times. Under automatic control, the BCM (body control module) selected the appropriate mode (air flow path), adjusted fan speed, modulated outlet air temperature and controlled air conditioning compressor operation. At any setting, the system gave occupants the same perceived comfort level regardless of outside conditions by altering the mode, fan speed and outlet air temperature. A small, motordriven fan drew air to the sensor from the passenger compartment through a grille in the face of the control. As in the past, the system also used a solar sensor on top of the instrument panel, an outside temperature sensor behind the front bumper and the engine coolant temperature sensor to determine appropriate air outlet temperature, fan speed and mode door positions. In automatic mode, the air conditioning compressor ran whenever outside air temperature was above about 32°F (0°C) to dehumidify the air for added comfort. This also greatly reduced condensation on the inside of the windshield and side windows. The solar sensor measured light intensity as a guide to automatic mode and air outlet temperature control. Five basic modes were provided as in the past: panel, bilevel, floor, mix and defrost, but 255 combinations were possible to enhance comfort. In cold weather, the BCM inhibited blower operation until a comfortable air outlet temperature could be provided and selected mix mode operation during warm up.

A patented algorithm in the ATC control system made minor adjustments in temperature primarily by changing outlet air temperature, and secondarily by increasing air flow the way customers typically adjust a manual system. This feature allowed the system to maintain desired comfort with less blower noise than the former algorithm, which always increased blower speed.

Another algorithm, used by the ATC system, maintained constant air flow regardless of vehicle speed. At highway speeds, air flow through the car was provided primarily by outside air pressure allowing a very low blower speed. On surface roads and in city traffic, the blower speed must increase to maintain the desired comfort level. Therefore, the new algorithm checks vehicle speed and adjusted Body Systems fan speed accordingly. This Chrysler-patented feature also used the positions of doors in the HVAC unit as inputs to determine the blower speed necessary to maintain proper flow.

A new control panel provided for either automatic or manual operation. It made automatic operation easier. Semi-automatic operation, which customers found difficult to understand, was eliminated.

The new control panel used rocker switches for temperature selection and all function selections except fan speed control, which remained a rotary knob. Pressing AUTO put the system into fully automatic operation. Pressing the opposite end of the AUTO rocker turned the system off completely. When the system was off, outside air did not enter the passenger compartment.

Pressing any mode button, the air conditioning compressor button, or the recirculation button placed the system under manual control. In manual control, the customer selected the comfort temperature, fan speed, mode and chose between air conditioning on or off using the control panel's rocker switches and the rotary fan speed knob. It operated in floor, bilevel and panel modes only. Even under manual control, the system worked to maintain comfort and safety in the following ways:

  • Interior temperature biasing to maintain interior comfort under varying outside conditions continues as with automatic control
  • Selecting recirculated air while in the panel mode automatically turned on the air conditioning compressor to help keep the windshield and side window from fogging and illuminated the "snowflake" icon in the display if outside temperature was below 50°F (10°C). Pressing the A/C button turns off the compressor again, if desired
  • The air conditioning compressor runs automatically in mix and defrost modes to aid in defrosting the windshield and side windows when the outside temperature is below about 32°F (0°C)

Buttons were illuminated through the graphics for nighttime operation. Fan graphics on the face of the control panel and the pointer on the fan speed knob were also illuminated. Graphics appeared white in daylight but illumination is blue green.

  • The display continuously indicated whether the system was under AUTO (automatic) or MANUAL control
  • Present mode (air flow path) selection was indicated at all times using five basic industry standard ISO icons
  • A car silhouette icon appeared when air was being recirculated
  • A "snowflake" icon appeared when air conditioning was selected
  • Attempting to select a temperature setting above or below the available operating range produced a display indication of HI or LO, rather than a reading in degrees. This indicated that the system was providing the hottest or coldest possible comfort setting

With ATC, a new blower control module had numerous linear speed increments and a relatively small step to maximum speed.

As in the past, ATC system diagnostic trouble codes could be viewed in the ATC display, allowing technicians to identify ATC problems without special scanning tools. Where malfunctions correspond with those of the manual HVAC system, the same diagnostic test codes were used.

The electronic controls automatically selected recirculated air flow when outside temperatures were extremely high. For temperatures in the 95-120°F (35-49°C) range, the control may also select recirculated air flow. Selection of automatic recirculation was based on refrigeration system internal pressure communicated to the control via the J1850 data bus. When selected, it enhanced occupant comfort and reduced compressor and system loads. This feature was patented.

A new defroster duct system provided faster, more uniform defrosting of the windshield.

Ducts in the center console delivered more air flow to rear seat passengers for added comfort.

A new duct system provided even air flow distribution while avoiding the cost of door-mounted outlets and duct work. A new housing for the passenger compartment HVAC components used computer-designed air flow passages and was quieter. The blower motor was quieter.

A more powerful rear window defogger cleared the glass quickly and uniformly.

Audio Systems

  • All functions were visible and clearly labeled
  • Separate knobs provided balance and fade control
  • Rotary knobs for volume, balance and fade provided precise control. Off-on/volume, balance and fade control knobs were recessed in the face of the control panel when not in use. The knobs popped out for adjustment when pressed, and returned to their recessed positions using the same action. Rotary balance and fade controls provided more precise control of speaker output than the former joystick. Pressing the off-on/volume control also turned the radio on
  • Ergonomically shaped buttons provided improved separation, actuation and feel. Buttons for all functions are cupped to fit one's fingers
  • Legibility and lighting of nomenclature and graphics was improved. All controls were lighted through the graphics, and displays were bluegreen vacuum fluorescent panels

Infinity® II System

    • Standard in Europe
    • A new 320-watt Infinity amplifier had nine output channels one, for each speaker location. Enhanced distortion limiting circuitry prevented over-driving the speakers.
    • A single 2.5-inch (64-mm) full-range, spatial imaging speaker mounts in the center instrument panel
    • Two 2.5inch (64mm) coaxial speakers mounted in the lower front corners of the front windows. These speakers were aimed at the front seat occupants on the opposite side of the car to provide clear sound without excess intensity. Grilles on these speakers included Infinity logos
    • Two 6.5-inch (165-mm) round full-range speakers were located in the front doors. Front door speakers were mounted somewhat higher than those of competitive cars for better sound projection. A raised seal on the face of each of these speakers pressed against the reverse side of the door trim panel, enhancing front-to-rear separation for better sound quality
    • Two 6 x 9 inch (152 x 229 mm) full-range speakers mounted beneath the rear shelf panel
    • Two 2.5-inch (64-mm) round speakers were placed in the rear doors. Mounted high in the doors, these speakers enhanced high frequency sound for rear seat passengers

A rear window-mounted antenna was standard on Chrysler LHS and 300M.

Interior Trim

A structural membrane adhesive bonded to the inside of the roof panel reduced interior noise by damping panel vibrations. Noise caused by rain and other conditions that could make the panel resonate were substantially less noticeable using this stiffening system than with conventional steel bows and/or splines. The structural membrane stiffened the whole panel to prevent resonance, whereas bows and splines provided only localized stiffening. This system was also lighter and less costly than steel bows. The substrate of the roof system, to which the foam-backed head-lining fabric and overhead components were attached, was made from sound insulating AcoustiCor®. The AcoustiCor headliners could be recycled again into a new material called EcoCor®.

Roof railmounted assist handles for the rear and right front passengers fit depressions molded into the roof system. The overhead console and other roofmounted components may be removed for service without disturbing the interior roof system.

Softer, more luxurious door trim panels resulted from the use of thicker foam backing for the vinyl surface in the bolster and armrest areas. The soft areas were also larger than on prior models. New deep, oval pull cups in the armrests provided ample finger clearance for a full grip. The side of each pull cup facing the interior of the vehicle was recessed to provide an even better grip. Opposite the recess, a subtle longitudinal depression in each trim panel surface enhanced the grip effect, providing the functional equivalent of a reach through handle with reduced cost and complexity.

All front door trim panels included map pockets and formed metal speaker grilles.

Rectangular depressions molded into the rear door trim panels were designed to accept ash receivers when the Smoker's Package was ordered, but also held juice boxes. When equipped with the optional Infinity® II audio system, rear door trim panels included speaker grilles.

A molded one piece needled fiber trunk liner covered the sides, back and floor, including the tire well. This material also lined the trunk lid. A separate carpeted spare tire cover provided a level storage surface. On LHS, a pull-down strap aided trunk closing.

Chrysler LHS and 300M also included the following new or refined interior trim items:

  • A molded plastic driver's left foot rest attached to the floor beneath the carpet to enhance comfort and stability
  • A grommet in the driver's floor mat that fit over a hook snapped into the carpet provided positive positioning and retention of the floor mat
  • Door weather strips had inboard lips that overlapped the interior trim in the openings, providing continuity across the interface for a finished appearance
  • The carpeted rear shelf panel had speaker openings in its resinated fiber substrate. Sound passed through the needled fiber carpeting

An optional smoker's package consisted of a cigar lighter, which was inserted in the standard power outlet, and two covered, removable rear ash receivers. The rear ash receivers were inserted in existing depressions in the door armrests. A front ash receiver was standard.

Cooling Systems

The new integrated cooling module combined the following units:

  • A new radiator
  • Updated air conditioning condenser with significantly greater heat transfer area to enhance cooling performance
  • Tandem transmission oil coolers in the radiator and externally mounted increased transmission cooling capacity 7% from prior levels
    • A new in-tank plate-type oil-to-coolant heat exchanger
    • Auxiliary oil-to-air heat exchanger
  • Redesigned dual cooling fans
  • Industry first integrated coolant hot bottle and overflow reservoir

Both fans ran simultaneously when needed. They ran faster and moved more air with less noise than previous platform vehicles. The coolant hot bottle, a feature carried over from prior models, provided a means to remove air from the circulating coolant.

New engine coolant used 100% post-consumer ethylene glycol with long life corrosion inhibitors. When diluted with distilled water, it allowed a change interval of 5 years or 100,000 miles (160,000 km). This new coolant was not compatible with propylene glycol.

Electrical & Electronic Systems

A standard Personalized Memory System that allowed two drivers to preprogram their individual power seat, power mirror and radio push button settings for instantaneous recall was available for the first time on Chrysler LHS and 300M. All seat settings vertical, horizontal, tilt and recline angle were included. The system was operated by individually programmed Remote Keyless Entry (RKE) transmitters and by switches on the driver's seat cushion outboard side shield. It worked with the seat, mirror, and radio settings.

The Body Control Module (BCM) had been upgraded to support the J1850 vehicle communications and diagnostics bus. It mounted directly on the junction block located in the lower, left cowl side. It was available in two feature levels base and premium. Only LHS used the premium controller.

The BCM provided the following new functions:

  • It controlled the exterior lamps (head lamps, fog lamps, parking lamps and tail lamps)
  • It included a Battery Saver feature that automatically turned off electrical loads if this was not done by the driver after a reasonable time.
  • It operated the manual HVAC system.
  • It actuated and timed electric rear window defogger (EBL) operation.
  • It provided central locking and a choice of unlocking modes. Unlocking the drivers door with the key unlocked that door only. However, if the key was returned to the "neutral" position and again turned to the unlock position, all doors unlocked. Unlocking the passenger door with the key immediately unlocked all doors
  • It operated the Remote Keyless Entry (RKE) system.
  • It provided speed proportional steering control (LHS only). The steering control electronics were now integrated with the BCM
  • It turned on the head lamps automatically when the wipers had been on for at least 10 seconds and the head lamp switch was in the automatic position
  • If the windshield wipers were on when the ignition is switched off, it kept the wiper motor running until the blades were in the parked position
  • It provided trunk release logic that prevented inadvertent opening. The trunk release button on the instrument panel and the trunk button on the RKE will open the trunk only under following "appropriate" conditions:
    • When the ignition was off
    • When the transmission was in 'Park' with the ignition on
  • It provided customer programmable rolling door locks. On vehicles with power door locks, the automatic feature was enabled when shipped from the factory. The Owner's Manual included instructions for enabling or disabling the feature by a simple sequence of ignition switch and power lock switch actions

A standard outlet for electrically powered accessories also operated a conventional cigar lighter unit (available from a dealer in the Smoker's Package) if desired. The outlet included a tethered cap labeled with its ampere and voltage rating.

A new industry standard data communications and diagnostics bus (SAE J1850) replaced the proprietary Chrysler (CCD) bus as the link through which on-board control modules shared information with each other and with offboard testers through a diagnostic connector. J1850 provided the following advantages over the CCD communications bus technology:

  • Used a singlewire bus rather than a twisted pair of wires
  • Transmits information between modules at two to three times the data rate
  • Used a more rugged transceiver circuit for improved reliability
  • Provided the capability for immediate acknowledgment that the message was received by the intended receiver
  • Allows one module to "wakeup" another module over the bus when the engine was not running, if required

The following modules communicate over the J1850 bus:

  • Instrument cluster
  • Body Control Module
  • Power Train Control Module
  • ABS Control Module
  • Overhead Travel Information System
  • Smart Key Immobilizer Module (midyear introduction)
  • Radio (except base cassetteplayer radio)
  • Automatic Temperature Control Module
  • Transaxle Control Module
  • Air Bag Control Module
  • Personalized Memory System Module (midyear introduction)

New wiring features were:

  • Optimized circuit partitioning and harness routing eliminated over 100 circuits and eight splices to lower cost and improve reliability. Using vehicle architecture and feature availability information during design, circuits with balanced loads are devised
  • Use of the new industry standard J1850 vehicle communication and diagnostics bus eliminated 17 circuits and eight "twisted pairs" required with the former CCD system
  • A new junction block eliminated over 35 circuits by providing direct, plug-in connections for the BCM, remote keyless entry (RKE) module and daytime running lamp (DRL) module
  • A snap-in panel on the left end of instrument panel provided access to the fuses and relays. Fuses were identified by diagram molded into the back of the snap-in panel
  • A new power distribution center (PDC) provided mounting for micro-relays and F-type cartridge fuses, which took less space than the components they replaced, permitting the PDC to house substantially more components in a slightly larger package than in the past. (This was Chrysler's first use of F-type cartridge fuses.)
  • Improved electrical grounding increased electrical system reliability. Separate grounding paths were used for low current circuits that carried electronic signals and high current power circuits. This protected the signal circuits from extraneous signals that could adversely affect their operation
  • Wire gauge and fuse size were optimized to ensure robust electrical system performance

Wire harness durability and freedom from BSRs was enhanced through improved routing and protection that included the following features:

  • Expanded use of weld studs, clips, troughs and foam tape protected wiring and kept it away from heat and damage
  • Easily accessible positive and negative terminals for the remote mounted battery facilitated assist starting (jumping). The remote positive terminal mounted behind the right head lamp. The negative terminal mounted on the right strut tower

Wiring connector improvements increased quality and reliability.


Total Vehicle NVH Control

Power Train

Engine sound remained clearly perceptible, especially under hard acceleration, but the sound was smooth and suggested power. Deflection and resonance in structural and dynamic components as the engine runs caused a major portion of objectionable engine noise. To minimize this occurrence, components were stiffened and, in the case of some dynamic components, made lighter to impose less force, thereby reducing noise. Quietness also stemmed from two other factors: reduction of vibration within the engine and prevention of noise transmission. Vibration was reduced by making structures stiffer and moving parts stiffer and lighter. Noise transmission was avoided by preventing outer surfaces from resonating with noises inside the engine valve train, camshaft drive chains, oil and water pumps, etc.

2.7Liter Engine

The 2.7 V6 engine provided the following noise preventing features and their associated benefits compared to the former 3.5 liter engine:

  • The forged steel crankshaft, engineered using FEA, had 26% greater torsional stiffness the stiffest crankshaft Chrysler had ever analyzed
  • The cast aluminum cylinder block provided 28% greater torsional stiffness. An exceptionally stiff block was produced through use of FEA studies that focused on torsional frequency, lateral bending, and torsional bending. The block included the following features:
    • Extensive ribbing
    • Sixbolt main bearing caps four vertical, two transverse. For quietness, the natural frequency of the bearing caps exceeded the firing frequency of the engine. Stiff bearing caps also reduced the potential for wear caused by deflection under load
    • Structural beam windage tray. It provided added support to the main bearing caps that helped increase overall stiffness
  • Rigid accessory drive mounting. The air conditioning compressor and alternator mounted directly to the block and structural oil pan, rather than on brackets. This prevented these heavy items from vibrating independent of the engine, adding input to the power train mounts. Only the power steering pump, which was the lightest of the accessories, still mounted on a bracket, but it was more compact and stiffer than former brackets. The new mounting arrangement provided the following accessory mounting stiffness improvements relative to the previous 3.5liter engine:
    • air conditioning compressor: 68% stiffer
    • Alternator mounting: 13% stiffer
    • Power steering pump mounting: 5% stiffer
  • More precise control of reciprocating masses and better balancing of rotating components reduced nominal engine unbalance by 27% from former levels. Pistons 14% lighter than before, relative to their bore size, were a major contribution to the improvement.

The 2.7liter engine included the following features that contributed to low noise transmission:

  • Low rumble intake manifold. The new design had three tuned intake runners from each bank of cylinders connected to its plenum chamber in a cluster or focal point. In conventional manifolds, the runners were equally spaced lengthwise along the plenum. The effect of the low rumble design was that standing air pressure waves occurring at the mouth of each runner were essentially "in phase," whereas with prior manifolds these waves were out of phase at low speed, resulting in a distinct rumbling sound that was audible in the passenger compartment
  • Ribbed block side.s While providing overall stiffness to the block, ribs broke up flat surfaces into small sections that were too stiff to resonate with engine internal noises
  • Isolated composite valve covers. Mounting of the cylinder head covers was completely isolated to prevent them from vibrating in resonance with the internal noise in the cylinder head. The covers were made of composite material that had inherent damping characteristics to further resist noise transmission

3.5Liter High Output Engine

The new 3.5-liter high output engine was significantly quieter than its predecessor. It incorporated the following noise preventing structural stiffness features, providing the indicated stiffness increase relative to the prior 3.5-liter engine:

  • The cylinder block had 11% greater torsional stiffness. High torsional frequency, torsional bending stiffness and lateral bending stiffness were engineered into the block using FEA. The following features contributed to the block's stiffness:
    • Extensive ribbing throughout its structure
    • Sixbolt main bearing caps four vertical, two transverse replace fourbolt caps used previously. They constrain the crankshaft to reduce deflection. The bearing cap's natural frequency exceeds the firing frequency of the engine. Stiff bearing caps also reduced the potential for wear caused by deflection under load
    • A structural beam windage tray replaced a nonstructural tray. It provided added support to the main bearing caps that helped increase overall stiffness
  • Lightweight pistons 15% lighter than before provided more precise control of reciprocating masses. Improved balancing of rotating components reduced nominal engine unbalance by 10% from former levels
  • Castaluminum cylinder head covers, which provided inherent noise damping, were completely isolated to prevent noise in the cylinder head from being transferred to the covers
  • Increased accessory drive mounting bracket stiffness prevented these heavy items from vibrating independent of the engine, adding input to the power train mounts. The new accessory mounting arrangement provided the following stiffness improvements relative to the prior engine:
    • Air conditioning compressor mounting: 52% stiffer
    • Alternator mounting: 33% stiffer
    • Power steering pump mounting: 24% stiffer

Shared Features

The LHS and 300M power trains incorporated the following noise preventing improvements compared to the prior 3.5-liter power train:

  • A structural oil pan, combined with a structural engine-to-transmission collar, provides a 41% stiffer connection. The oil pan also added stiffness to the cylinder block
  • Added structural ribbing increased transmission case stiffness 14%
  • The transmissiontocradle mount was stiffened through increased structural ribbing and revised mounting attachment
  • Select fit engine main bearings reduced operating clearance
  • Cylinder block water flow passages designed using CFD helped maintain uniform temperatures during warmup, keeping cylinders round for quiet operation
  • Refined dual, hydroelastic power train mounts, which used a combination of soft rubber elements and hydraulic damping made the engine mass a ride damper, contributing to a solid ride
  • Lower alternator operating speeds and revised alternator fan geometry reduced high speed fan noise
  • Stiffer alternator housings minimized low speed magnetic noise
  • A refined air induction system produced 15% less noise at the air inlet with a more pleasant sound than the prior system. By comparison, components were larger and located more appropriately for proper tuning than their predecessors. Major elements included:
    • An "ideal" entry an opening that smoothed entering air flow outside the engine compartment between the right front fender and wheelhouse liner
    • A Helmholtz resonator attached to the side of the inlet air duct that was tuned to damp out objectionable noise in a narrow frequency range
    • An inline resonator to control noise across the full spectrum intake air frequencies radiating to the passenger compartment

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