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 upModel-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 EmpowerChrysler Group’s expanding product lineup demands
new engines. So powertrain engineers delivered four new ones – or is it
five?
6.4-liter HEMI® V-8The 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-6The
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-6The 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.