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Vaguely badass...
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Chrysler LLC Press Release said:
World-First Driveline, Breakthrough Transmission, Four New Engines Mark Milestone Model-Year for Chrysler Group
World’s first front-wheel-drive-based 4x4 system with rear-axle disconnect
World’s first nine-speed automatic transmission – one of three new gearboxes
New 6.4-liter HEMI® V-8, mightiest gasoline engine in heavy-duty pickup segment
New 3.0-liter EcoDiesel V-6 – lone diesel engine in light-duty pickup segment
New 3.2-liter Pentastar V-6, derived from award-winning 3.6-liter Pentastar
New 3.0-liter EcoDiesel I-4 commercial truck engine
June 28, 2013 , Chelsea, Mich. - Chrysler Group mashes the throttle on engine, transmission and driveline debuts for model-year 2014.

The introductions, which span multiple model lines, send a clear message to the world.

“We are steadfast in our commitment to innovate for the benefit of our customers,” said Mircea Gradu, Vice President — Powertrain Transmission and Driveline Engineering and Head of Virtual Analysis. “Nowhere is this more evident than on the all-new 2014 Jeep® Cherokee.”

The all-new Cherokee’s stylish appearance belies the rugged capability delivered by its unique 4x4 system.

It is the first mid-size sport-utility (SUV) to feature a front-wheel-drive-based rear-axle disconnect system. It delivers four-wheel traction whenever it’s needed, without driver intervention.

A fully variable wet clutch housed in the rear drive module supplies the proper amount of torque for any traction condition. This capability also is a boon to aggressive starts.

Sophisticated algorithms enable the system to benefit driving dynamics by interacting with electronic stability control (ESC). When conditions are more favorable, it seamlessly switches to two-wheel-drive for optimum efficiency.

The system is available with either a one- or two-speed driveline (PTU and RDM). A locking differential is available with the two-speed PTU.

In low range, the 2.92:1 gear reduction also sets up aggressive crawl ratios – 56:1 when the vehicle is powered by the 2.4-liter Tigershark I-4 engine, and 47.8:1 when powered by the new 3.2-liter Pentastar V-6. Such specifications benefit off-road performance.

An available locking rear differential enhances control in extreme off-road conditions and is selectable in any low-range terrain mode.

Geared up
Model-year 2014 also marks the world debut of Chrysler Group’s nine-speed automatic transmission.

The advanced-technology gearbox enables aggressive launches, smooth power delivery at highway speeds and greater fuel efficiency than a six-speed automatic transmission. Its ratios are:

1st – 4.71
2nd – 2.84
3rd – 1.91
4th – 1.38
5th – 1.00
6th – 0.81
7th – 0.70
8th – 0.58
9th – 0.48

The wide ratio spread delivers outstanding low-end performance while small gear-ratio steps contribute to smooth transitions. Four overdrive ratios benefit highway fuel economy and reduce overall noise, vibration and harshness (NVH) levels.

The all-new, fully electronic nine-speed automatic features on-the-fly shift map changing with manual-shifting capability via Electronic Range Select. More than 40 shift maps correspond to specific conditions to optimize shift quality and shift points for improved fuel economy, performance and drivability.

To determine the appropriate shift mode, the sophisticated software accounts for variables such as engine torque gradients, kick-down events, longitudinal and lateral acceleration and grade changes. For improved driving comfort and refinement, additional parameters integrated into the transmission control strategy include: temperature, speed and electronic stability control. The result is automatic shifting attuned to the performance requirements of almost any driving situation.

Internally the transmission has four gear sets and six shift elements – multi-disc clutches, dog clutches and brakes. Only two friction-plate clutches are open in every gear, minimizing power loss.

Other new transmissions are the AS66RC six-speed automatic featured in 2014 Ram chassis cab models, and the M40 six-speed automated manual in the all-new Ram ProMaster full-size commercial van.

Sourced from Aisin, the AS66RC allows for optional 45HP and 250 lb.-ft. left- or right-side PTO. Paired with the HEMI®, efficiency is improved with Fuel Saver cylinder deactivation operation while in PTO mode.

The new M40 automated manual is mated to the 3.0-liter EcoDiesel I-4 in the ProMaster. The unique gearbox delivers the efficiency of a manual transmission with the functionality of an automatic.
At its core, it is a manual, but gearshifts and clutch functions are accomplished with an electro-hydraulic actuation system.

However, the driver can opt for manual shift-lever inputs when desired. But the driver needn’t do all the work. Shift logic is adjusted according to grade steepness so the gearbox responds intuitively to driving conditions.

New Engines Empower
Chrysler Group’s expanding product lineup demands new engines. So powertrain engineers delivered four new ones – or is it five?

6.4-liter HEMI® V-8
The all-new 6.4-liter HEMI® V-8 is actually two engines. Chrysler Group is producing one version for Ram HD pickups and another for Ram Chassis Cab models.

Each is optimized for its respective duty cycle. Both are expected to provide Ram with best-in-class bragging rights among gasoline-powered competitors.

The new 16-valve engine will make 410 horsepower (306kW) at 5,600 rpm while generating peak torque of 429 lb.-ft. (582 Nm) at 4,000 rpm.

The legendary HEMI architecture provides the foundation of the 90-degree V-8. But its advanced technology is decidedly forward-looking.

Cooled exhaust-gas recirculation (EGR) delivers greater efficiency and elevated refinement. These attributes are manifested in reduced pumping losses and lower emissions. Pumping losses are further reduced by variable-valve timing (VVT).

Efficiency is a hallmark of the new 6.4-liter HEMI V-8, starting with Chrysler Group’s celebrated Fuel Saver cylinder-deactivation technology. When conditions allow, as in highway cruising, the system seamlessly shuts down four cylinders to conserve fuel.

Upgraded valve-seat material, aluminum cylinder heads, a forged-steel crankshaft and a cast-iron block contribute to durability.

Computational fluid dynamic simulations were employed to optimize the cooling circuit in the block, heads and water pump. Other features that mitigate heat include a robust/high-volume oil cooler, oil jets for piston cooling and – in the HD pickup application – a stainless-steel exhaust manifold and sodium-filled exhaust valves.

3.0-liter EcoDiesel V-6
The new 3.0-liter 24-valve, dual-overhead-cam (DOHC) EcoDiesel debuts in the 2014 Jeep® Grand Cherokee and 2014 Ram 1500. It is a turbocharged 60-degree V-6 that generates 240 horsepower at 3,600 rpm and makes torque like a V-8 – 420 lb.-ft. at 2,000 rpm – without V-8 fuel consumption.

The new turbo diesel is designed and produced by VM Motori, a Chrysler Group diesel engine supplier since 1992.

The engine is shouldered by a bedplate and cylinder block of Compacted Graphite Iron (CGI), which is engineered to deliver higher strength. This enhances durability and reduces noise, vibration and harshness – a focus of many EcoDiesel design features, such as its structural aluminum oil pan.

The EcoDiesel’s 60-degree cylinder-bank angle and 1-2-3-4-5-6 firing order are optimized to manage inertia and firing loads, eliminating the need for a balance shaft.

Durability is further ensured by the EcoDiesel’s forged steel crankshaft and connecting rods – which provide additional NVH benefits – and its aluminum alloy pistons. These pistons, which benefit from cooling oil jets, reduce reciprocating mass inside the engine for enhanced efficiency and performance feel.

The EcoDiesel V-6 features Fiat’s innovative MultiJet II common-rail fuel-injection system. High-dispersion nozzles enable fuel-injection events that occur with greater precision up to eight times per cylinder cycle.

The interval between two consecutive injections also is better modulated to mitigate noise and benefit fuel consumption and emissions reduction. This is known as Injection Rate Shaping.

The new EcoDiesel V-6 achieves 50-state emissions compliance. A key enabler is the engine’s cooled Exhaust Gas Recirculation (EGR) system, which is controlled by an electric valve instead of the conventional pneumatic variety.

A state-of-the-art Selective Catalytic Reduction (SCR) system also reduces emissions. It incorporates a unique Diesel Exhaust Fluid (DEF) system that, unlike competitive systems, alerts the driver to low DEF levels while also allowing the engine to maintain full power.

Other features include an insulated DEF tank with heated lines mitigates the effects of cold-weather operation and an exhaust-system strategy that reduces soot output while also improving fuel economy and meeting emissions standards

The DEF tank holds eight gallons of fluid. Duty cycle determines refills, but the average interval is about 10,000 miles. DEF is commonly available fuel stations and is also offered by Mopar, Chrysler Group’s dealer network and Cummins dealers and distributors.

The standard engine oil cooler, when the EcoDiesel is used with 5W30 synthetic oil, contributes to a 10,000-mile oil-change interval. The use of B-20 biodiesel is validated and approved for the new 3.0-liter EcoDiesel.

3.2-liter Pentastar V-6
The new 3.2-liter Pentastar V-6 bows in the all-new 2014 Jeep® Cherokee. It carries over all the design features that make smooth power delivery one of the most captivating traits of the 3.6-liter Pentastar V-6, named one of Ward’s 10 Best Engines three years running.

A 60-degree, deep-skirt, die-cast-aluminum cylinder block with six-bolt main caps afford optimal stiffness for mitigation of NVH. Also contributing to NVH reduction are:
A structural windage tray to complement block stiffness
A structural aluminum oil pan
Direct-mounted alternator and A/C compressor that increases stiffness
Select-fit pistons with polymer-graphite-coated piston skirts
“Silent chain” timing drive with inverted teeth for minimal sprocket NVH
Contoured composite cylinder-head covers
Glass-reinforced nylon composite intake manifold

Further enhancing the driving experience is the specially designed intake manifold, which also featuers low-rumble tuning.

The Jeep Cherokee’s V-6 engine boasts forged-steel connecting rods and piston-squirter jets, and its cam drive and valve-train components require no scheduled maintenance.

The new 3.2-liter Pentastar V-6 engine was subjected to 3.3 million customer-equivalent miles prior to production.

3.0-liter EcoDiesel I-4
The 2014 Ram ProMaster full-size commercial van marks the North American introduction of the potent 174-horsepower 3.0-liter inline 4-cylinder EcoDiesel engine that generates peak torque of 295 lb.-ft. at just 1,400 rpm.

Designed by Fiat, which employs the engine in numerous applications including Class 2, 3 and 4 commercial vehicles, the 16-valve, dual-overhead cam I-4 has been adapted for the North American market with a wide range of modifications that enable regulatory compliance, while also enhancing performance.

A new common-rail fuel-delivery system managed by the engine control unit (ECU) allows for variable timing and duration of multiple fuel-injection events. The combined effect of the extreme injection pressure and optimized injection strategy mitigates emissions, improves fuel economy and offers significant reduction in noise, vibration and harshness (NVH).

Further refinement comes from a host of design features, such as:
Hydraulic tappets and roller-finger followers for valve-lash mitigation and friction reduction
Cast-iron engine block stiffened by bed-plate construction
Lightweight alloy pistons
Dual-mass flywheel
High-efficiency exhaust-gas recirculation (EGR) cooler (which also benefits emissions compliance)

Also new for North America is a quick-response variable-geometry turbocharger that delivers higher boost at low engine speeds. The result is improved driving satisfaction that comes from superior throttle response.

The engine’s block has been modified to accommodate a heater, which is standard equipment in Canada and optional in the U.S. The block heater improves cold starts at temperatures as low as minus 40 degrees, the same threshold as the transmission heater on the economical M40 automated manual gearbox that is exclusive to the turbo diesel.

To comply with emissions standards, the engine combines the benefits of a new EGR module with a highly efficient after-treatment system.

The urea diesel exhaust fluid (DEF) is integrated with heated lines. The five-gallon DEF tank promises nearly 4,000 miles of service. Low-level warnings alert the driver to replenish the supply via a filler neck conveniently adjacent to the optional locking fuel cap.

Reduced total ownership cost is a primary objective of the engine’s design. Key components from the camshaft chain drive to power-steering pump to the high-pressure fuel pump with automatic tensioner (which also benefits NVH) are designed for long life.

Similarly, thoughtful innovations such as wear-resistant cylinder liners, oil-cooled pistons and electronic engine-control units for continuous diagnosis and monitoring are specifically designed to ensure durability.
 

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The ratios for gears 2, 3, and 4 (in the nine-speed), must have been selected by engineers with a very poor throwing arm tossing darts at a dart board; even the 8 speed with less ratios, (and mostly hooked up with bigger engines than the nine-speed which will be mated to many 4-cylinder engines), mated to 6 and 8 cylinder vehicles, has better 2nd, 3rd, and 4th ratios for bottom end acceleration.
 

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I disagree. Depends on the axle ratio. Compare with an old Torqueflite (2.45, 1.45 and 1.00). The 9-speed's 4th gear is roughly equal to 2nd gear in a Torqueflite, which was attained around 15-18 mph in moderate driving. The 7th gear is equal to 4th (top gear) in my RH42 in my truck. This 9-speed should leap off the line with its aggressive 1st gear, drill quickly to 4th gear while staying in an optimum power band, and be in 7th gear routinely on the highway, with flat, steady driving allowing 9th gear, which will cut RPMs to a gas-sipping 1400 RPM or so. I love it.
 

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i must admit to being surprised at all the overdrive ratios...good or bad.
 

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This is all good information and good news, but the burning questions remain about the hemi engines mates with an 8 speed automatic. Has anyone leaked any performance numbers about the L cars such as mpg, 0-6, 1/4 mile, etc?
 

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redhed said:
i must admit to being surprised at all the overdrive ratios...good or bad.
They're good. The ratios in this transmission were beautifully done. You have an ultra wide 9.8:1 ratio spread. The ratios are extremely close together, and if you crunch the numbers - the % change between ratios gets smaller as you go up in gears, meaning at higher speeds shifts will be nearly imperceptible. So hunting should not be a problem.

Since the OD is so tall, you can use really low final drive ratios. In fact, if you look at the ratios Chrysler listed (2.92 low range, 4.7: 1st and the crawl ratio listed) you can work out that the 2.4 Cherokee actually has a 4.08:1 final drive ratio. Very low. The Tigershark 2.4 Cherokee will be able to put down almost as much torque to the wheels in 1st as a Hemi 300C. The 3.2L Cherokee with its 3.48:1 final drive will actually be able to put down 1000 lb-ft more torque than a 3.6 300c 5 speed to the wheels in 1st. It actually can still just barely out-torque the 3.6 8-speed LX cars in 1st!

The Cherokee with either engine will have no issues at all getting off the line.
 

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but cruising through hilly country with the cruise on won't be much fun...lots o shifting going on! but of course it will be less noticeable vs old tech trannies...
 

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redhed said:
but cruising through hilly country with the cruise on won't be much fun...lots o shifting going on! but of course it will be less noticeable vs old tech trannies...
I am sure the microcontroller has things worked out nicely. I wouldn't be worried. These aren't the transmissions we've been used to getting. The old ones will seem like they were filled with crushed glass instead of lube, by comparison.
 

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Hurry and get your 2013 $20K 3.6 Caravan while you still can. The largest motor at zero cost option is a bargain of the lifetime.
 

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Bob L., let's compare the ratios in the Journey when it was introduced with a six-speed in 2009 with the 2014 Cherokee. Journey, 3rd gear ratio 2.28, transaxle ratio 3.43, overall ratio 7.8 (wheel size for Journey and Cherokee both 17"I think, so tire size may be reasonably close). The newer Journey's trans axle ratio is 3.16, for an overall ratio of 7.2 in third gear, still much higher than what it works out to be in the new Cherokee with the nine speed.

Cherokee with 9 speed and V-6(I haven't seen the axle specs for the Dart with the nine speed, only for the current six speed). Third gear ratio 1.92, tranaxle ratio 3.2, overall ratio 6.14; not even close to what Chryc used for the six-speed, let alone a transmission with three extra gears. For quick acceleration from a standing start I prefer my vehicles to top off in third in the low-mid seventies, not mid eighties. Why do we need a third gear that can hit 85 mph?

The whole point (at least for me), for multi-speed transmissions was to have your cake and eat it too, ie, much better ratios in gears 1-3 for quick acceleration and geared very high at the top end to keep the rpm low at highway cruising speed to improve fuel mileage. The nine speed certainly is geared very high, however five gears from direct to the top ratio to me seems just a tad excessive; four would have been ok. The eight speed has only three gears from direct to the top ratio so originally I was expecting the nine speed to maybe have one more overdrive ratio, not two more.
 

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The 62TE ratio spacing is poor. 2nd and 3rd are ridiculously close together, much closer than they need to be. Then there is this huge weird gap to 4th that kills acceleration and makes for poor passing power. You can feel it around town, as the transmission shifts often between 3rd and 4th at slower speeds. The 62TE has a 19.7% increase in ratio from 2-3rd, then a 36.5% increase from 3rd to 4th, totally bizarre.

The ZF9 fills in the weird gaps the 62TE has, and its deeper overdrives allow for lower (higher numerically) final drive ratios, making up for ~2-3rd not being as low as the 62TE.

There is nothing wrong with a 3rd gear that takes you out to 80 MPH at the end of a 6500 RPM redline. I mean, the current 5 speed Hemi rams do over 85 MPH in 2nd.
 

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willy said:
Bob L., let's compare the ratios in the Journey when it was introduced with a six-speed in 2009 with the 2014 Cherokee. Journey, 3rd gear ratio 2.28, transaxle ratio 3.43, overall ratio 7.8 (wheel size for Journey and Cherokee both 17"I think, so tire size may be reasonably close). The newer Journey's trans axle ratio is 3.16, for an overall ratio of 7.2 in third gear, still much higher than what it works out to be in the new Cherokee with the nine speed.

Cherokee with 9 speed and V-6(I haven't seen the axle specs for the Dart with the nine speed, only for the current six speed). Third gear ratio 1.92, tranaxle ratio 3.2, overall ratio 6.14; not even close to what Chryc used for the six-speed, let alone a transmission with three extra gears. For quick acceleration from a standing start I prefer my vehicles to top off in third in the low-mid seventies, not mid eighties. Why do we need a third gear that can hit 85 mph?
The first two gears (overall) in all versions of the new 2014 Cherokee are more agressive (for better off the line acceleration), than a current Journey.

........2012 Journey V6/I4.......Ovrl...'14 Cheroke V6.....Ovrl..Chero V6/Tow...Ovrl.....Chero I4........Ovrl...Chero I4/Tow.....Ovrl
Axle ratio.................3.16...........................3.251............................3.517.........................3.734.......................4.048.............
1st.........................4.127......13.04..............4.71......15.32..............4.71.....16.58..............4.71....17.60............4.71....19.08
2nd........................2.842.......8.98..............2.84........9.23...............2.84.......9.99..............2.84....10.60............2.84....11.49
3rd........................2.283........7.21..............1.90........6.18...............1.90.......6.68.............1.90......7.09............1.90.......7.69
Last.......................0.690........2.18..............0.48.......1.56................0.48......1.69..............0.48......1.79............0.48.......1.94
 

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My "complaint" with the nine speed is third gear is too high, and the step between 3rd and fourth is quite high, as well as the big step between 1(4.7) and 2 (2.84). I prefer the eight speed for gears 1-4 and the closer steps from 4.7 to 1.67 especially if you're running 3.55s, or even 3.23 in the trucks.
As for top speed in third, I could mention the old three speeds with a 2.45 first gear (back in the 60s), could do almost 60 in 1st gear but that doesn't make for quick acceleration.
 

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And... the five speed with the Hemi may very well do 80 mph in second gear, but that's exactly the reason I would never even consider buying that vehicle with the pre-historic transmission. The Hemi with the eight speed with its much better bottom gears will blow the doors off the Hemi with the five speed. Even the V-6 with the eight speed is almost as quick as the much bigger Hemi and five speed.
 

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Honestly - how quick does your acceleration need to be? If you drag race for a living, that's one thing.

For it's intended applications - specifically the Cherokee and the minivans at this point - acceleration doesn't appear to be the focus.

Dart is a different story - but even then - aside from the GT - how quick does it really need to be for daily driving?
 

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willy said:
The ratios for gears 2, 3, and 4 (in the nine-speed), must have been selected by engineers with a very poor throwing arm tossing darts at a dart board; even the 8 speed with less ratios, (and mostly hooked up with bigger engines than the nine-speed which will be mated to many 4-cylinder engines), mated to 6 and 8 cylinder vehicles, has better 2nd, 3rd, and 4th ratios for bottom end acceleration.
You lost me when you insult the engineers about a transmission design when you have never even been able to try it out yet. Seems to me your the one tossing the darts.
 

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Seems to me, an aggressive 1st gear ratio helps the car leap off the line and very quickly get to its power band. I'll bet it's a good choice for city driving as well. Since 2nd gear is a higher ratio than 1st gear on a Torqueflite, I don't see it bogging down when it shifts.

The fire trucks I drove had a 1st gear ratio of 5.08:1. That really helped in getting it moving briskly from a stop. There was a fair drop in 2nd gear, but it was never felt performance-wise.
 

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willy said:
... Even the V-6 with the eight speed is almost as quick as the much bigger Hemi and five speed.
The 3.6 with the 5 speed is nearly as quick as the 5.7 behind the 5 speed, in identically equipped JKU's.
I'd give more credit to the 3.6 than to the 8 speed.
The 8 speed IS a more efficient way to transfer power, but it's only approx. 11% better and other factors contribute to "quickness".
 
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