The Jeep Grand Cherokee, second generation: 1999-2004 Jeep WJ
The first-generation Jeep Grand Cherokee was redesigned in 1999, to lower cost while raising performance and reliability; it was Chrysler’s first use of an electronic bus to replace individual wires throughout the body.
From its new V-8, Chrysler's first in three decades, to its five-speed automatic transmission, this was a Jeep with market-leading technology.
The 1999 Grand Cherokee was officially introduced June 16. At the time of the 1999 model’s introduction, the 1998 Grand Cherokee was the second best selling SUV — the best selling SUV you'd actually want to take off road.
Developed in 28 months for $2.6 billion, the 1999 Grand Cherokee was truly new, with only 127 carry-over parts (mostly fasteners). It looks similar to the 1998 model, but with sleeker, softer shapes; demand was strong, and Jeep was taking no chances. Chrysler did move the spare tire under the rear floorboard to create more storage space, and without forcing drivers with flat tires to get under the car.
1999 Grand Cherokee drivetrain
A new, Jeep-inspired 4.7-liter V-8 was lighter, more efficient, and cheaper to build than the aging 318 (5.2). Export Jeeps had a VM 3.1-liter, five-cylinder turbo-diesel, a step up from the old VM 2.5-liter diesel.
4.0 liter six cylinder engine
The 4.0-liter AMC six-cylinder was retuned for quieter operation, with power going up by 10 hp (to 195 bhp/145 kW) for Federal or European Stage II emission standards. California's LEV (Low Emission Vehicle) capable engines, which slashed emissions by 30%, still gained five horsepower (3.75 kW) to 190 bhp (142 kW).
The engine had a cast iron block and head with two valves per cylinder. A new slitter-vane water pump was 50% more efficient, good for two horsepower (1.5 kW) on its own.
A new elastomer-coated steel intake manifold gasket, a two-piece high silicon-molybdenum alloy cast-iron exhaust manifold and a new multi-layer steel exhaust gasket doubled the expected life over the previous components.
Separation of the exhaust manifold into two pieces reduced internal stress. An automated belt tensioner and coil-on-plug ignition improved durability and reduced service needs.
The new intake and exhaust manifolds enhanced the sound quality of the engine and produced a lower, "throaty" sound preferred by customers. Fine-tuning, including a new laminated oil pan, made the engine 5dB quieter — though it was still noisy especially compared with the new V8.
Jeep five-speed automatic transmission
An electronically-controlled transmission with five forward ratios (including an alternate second gear ratio for passing), the 545RFE, was available with the V-8 only. The transmission had a tall, 3.00:1 first gear for better initial acceleration. Real-time adaptive shifting fine-tuned the shift pattern to the driver. Depending on speed and throttle position, both the 1.67 and alternate 1.50 second gear ratio were available for kick-down. The reverse gear ratio was equal to the first gear ratio, to allow for heavier loads.
The 545RFE’s three planetary gear sets combined the widest range of gear ratios available in any transmission in its class. The transmission was built at the Indiana Transmission Plant in Kokomo, Indiana, in a 1.2-million square-foot (110,000 m2) facility.
A new four-wheel drive system, Quadra-Trac II, used a progressive, speed-sensing torque transfer differential — the first industry use of Vari-Lok axles in both the front and rear axle. The Quadra-Drive system kept the vehicle moving even if only one wheel has minimal traction, and worked without straining, wearing or compromising the anti-lock braking system.
Quadra-Drive II was standard with the V-8 and optional on the six (Jeeps made in Austria had Quadra-Drive standard).
The Quadra-Trac II transfer case normally sent most of the power and torque to the rear wheels. The moment a wheel lost traction, a gerotor pump applied hydraulic pressure to a multi-disc clutch pack, sending power to the front axle.
The gerotor pump used a rotor driven by the front drive shaft and the case by the rear drive shaft, creating a pressurized oil flow to the clutch pack in proportion to their speed variation. Clutch discs were alternately splined to the front and rear drive shafts. Because Quadra-Trac II could immediately pressurize the clutch pack, it had a faster response than a viscous coupling. (Quadra-Trac II’s low range had a 2.72:1 torque ratio and fully locked the center differential).
A similar pump was in the Vari-Lok differential; power transfer was proportional to wheel speed difference, rather than torque difference. By avoiding the need to pre-load the differential to assure torque transfer, the Vari-Lok could be virtually wear-free. Vari-Lok differentials responded more quickly and smoothly than viscous-coupling systems, and the pump response could be precisely tuned to driving conditions, enabling the use of this advanced system in the front axle as well as the rear.
New rear suspension, revised front suspension
The 1999 Grand Cherokee had a new three-link rear suspension with lower unsprung weight and a higher roll center, with a revised front suspension. New tubular front and rear control arms were hydro-formed, making them five times stiffer. Modified coil springs were used for all (now 16”) wheels. Solid axles provided constant camber.
The new rear suspension let the Jeep corner flatter, while wider spacing of the tie-rod points helped smooth low-speed turns, with crisper turn-in response, better on-center steering feel, and reduced tire wear. Changing the track bar geometry resulted in less lateral motion, for much lower head movement on bad roads. Repositioning the steering linkage helped “feel” and response.
The new, integrated anti-lock braking system with electronic brake distribution (EBD) was lighter and less complex, with less pedal pulsation and fade, and better front/rear balance; the Jeep had the largest brake rotors in its segment.
The suspension had 8.3 inches (210 mm) of travel in motion. Even over bumps, the axles maintained their class-leading ground clearance of 9.3 inches (237 mm) and 8.3 inches (210 mm), respectively. An optional Up-Country suspension package (for both Laredo and Limited) increased ground clearance by one inch (25 mm).
As with every Jeep, the 1999 Grand Cherokee was designed to cross standing water up to 19 inches (480 mm) deep. The Jeep met all passenger-car safety requirements — not just those for light trucks.
Grand Cherokee changes
For 2000, the Jeep Grand Cherokee continued its successful journey forward, wowing critics and buyers with its satisfying ride and feel, “despite,” critics would say, “that antiquated, non-buzzword-compliant suspension.” There were minor cosmetic changes to the interior, including redesigned air outlets and better gauge pointer lights; two wheel drive and Selec-Trac became available with the 4.7 liter V8.
In 2001, the long-running Jeep Cherokee, which was supposed to have been replaced by the Grand Cherokee in 1993 and then by the Jeep Liberty in 2000, was finally dropped in June 2001, after a last burst of sales. It had lasted nearly a year longer than intended, running down the assembly line at the same time as its two replacements.
Meanwhile, the Grand Cherokee got a hefty facelift to deal with increased competition:
- New options and equipment groups were added, including stereo upgrades
- The 4.7 liter engine came standard with the 545RFE five-speed automatic transmission (which had been optional), and a hydraulic fan which raised gas mileage slightly.
- Wheels were bumped up from 16 to 17 inches
- A quarter-turn gas cap and child seat tethers were added.
- Limited got new seats with gathered leather, additional color-keyed trim, and aluminum-finish gauges. The Laredo got brushed aluminum dashboard trim.
- A cargo net was standard for the left quarter trim panel.
- A connector for aftermarket electric trailer brakes was added to the tow group.
When the Canadan Auto Association asked members “What is the vehicle of your dreams?”, the most common choices of Canadian respondents was the Jeep Grand Cherokee (others in the top ten were the Dodge Durango, Chrysler PT Cruiser, Dodge Caravan, and Dodge Ram).
2002: Jeep Grand Cherokee Overland debuts
2002 MSRP incl. destination Price Grand Cherokee Laredo 2WD $26,100 Grand Cherokee Laredo 4WD $28,070 Grand Cherokee Sport 2WD $26,025 Grand Cherokee Sport 4WD $27,995 Grand Cherokee Limited 2WD $30,945 Grand Cherokee Limited 4WD $33,375 Grand Cherokee Overland 4WD $37,505
- Four wheel drive only with high-output V8, Quadra-Drive®, and “up country” suspension
- Luxury trim including rear redwood burl
- Standard power pedal adjusters with memory, rain-sensitive wipers, and 10-disc CD changer
- P235/65R17 Goodyear Wrangler SR-A all-terrain tires
- Full-size spare tire with matching wheel
- Inflatable curtain supplemental side air bags
- Overland’s high-output V-8 (260 hp, 330 lb-ft torque) was also optional on Limited with K package, which included Wrangler F1 Ultra all-season performance tires.
- Vari-Lok rear differential replaces Rear Trac-Lok® (on cars without Quadra-Drive®
- Optional tire pressure monitor system with actual pressure readings
- Thermal Expansion Valve added to air conditioning system to enhance cool-down
- New Laredo seat fabric and appearance
- Electroluminescent cluster lighting standard on Limited and Overland
- Optional pedal adjustment optional (with memory on Limited)
- Optional airbags for both front and rear seats; all airbags upgraded
2003: major changes for the penultimate year
The main changes for the 2003 model year included:
- Available roof rack cross rails
- Reduced-pressure shocks for improvements in overall ride comfort
- Reduced brake pedal effort (via higher master cylinder output pressure)
- New brake calipers for 2003 for smoother and more linear braking
- Reduced steering effort by a 20%, thanks to a revised steering gear torsion bar.
- Standard, multi-stage driver and passenger front air bags were designed to deploy at different levels depending on the severity of the impact.
- Jeep Grand Cherokee Laredo had new high-back cloth seats (low-backs were still available)
- A new cubby bin for holding sunglasses or phones replaced the ashtray.
Jeep moved an incredible 207,479 Grand Cherokees in 2003, versus 30,000 Mercedes M-class.
2004: the final year of the “real” Jeep Grand Cherokees
In its final year, Jeep sold 182,313 Grand Cherokees. Its replacement would arrive in 2005, a joint engineering project with Mercedes; reportedly Jeep retained control of the four wheel drive systems, while Mercedes demanded suspension changes and influenced the body structure. Mercedes would sell their version as the ML.