torque JEEP GRAND CHEROKEE 2007 WK / 3.G Owners Manual

WARNING!
ABS (Anti-Lock Brake System) cannot prevent the
natural laws of physics from acting on the vehicle,
nor can it increase the traction afforded by prevail-
ing road conditions. ABS cannot prevent accidents,
including those resulting from excessive speed in
turns, driving on very slippery surfaces, or hydro-
planing. Only a safe, attentive, and skillful driver
can prevent accidents. The capabilities of an ABS-
equipped vehicle must never be exploited in a reck-
less or dangerous manner which could jeopardize
the user’s safety or the safety of others.
TCS (Traction Control System)
This system monitors the amount of wheel spin of each of
the driven wheels. If wheel spin is detected, brake
pressure is applied to the slipping wheel(s) and engine
power is reduced to provide enhanced acceleration and
stability. A feature of the TCS system functions similar to
a limited slip differential and controls the wheel spin
across a driven axle. If one wheel on a driven axle is
spinning faster than the other, the system will apply the
brake of the spinning wheel. This will allow more engine
torque to be applied to the wheel that is not spinning.
This feature remains active even if TCS and ESP are in
either the “Partial Off” or “Full Off” modes. Refer to “ESP
(Electronic Stability Program)” in this section.
130 UNDERSTANDING THE FEATURES OF YOUR VEHICLE

Overdrive Operation
The automatic transmission includes an electronically
controlled Overdrive (5th gear for 3.7L engine, 4th and
5th gears for 4.7L and 5.7L engines). The transmission
will automatically shift from direct gear to Overdrive if
the following conditions are present:
•the transmission selector is in D (Drive);
•the engine coolant has reached normal operating tem-
perature;
•vehicle speed is above approximately 30 mph (48
km/h);
•the “TOW/HAUL” button has not been activated;
•transmission has reached normal operating tempera-
ture.
NOTE:If the vehicle is started in extremely cold tem-
peratures, the transmission may not shift into Overdriveand will automatically select the most desirable gear for
operation at this temperature. Normal operation will
resume when the transmission fluid temperature has
risen to a suitable level. Refer also to the Note under
torque converter clutch, later in this section.
During cold temperature operation you may notice de-
layed upshifts depending on engine and transmission
temperature. This feature improves the warm up time of
the engine and transmission.
If the transmission temperature gets extremely hot, the
transmission will automatically select the most desirable
gear for operation at this temperature. If the transmission
temperature becomes hot enough, the “TRANSMISSION
OVER TEMP” message may display and the transmis-
sion may downshift out of Overdrive until the transmis-
sion cools down. After cool down, the transmission will
resume normal operation.
258 STARTING AND OPERATING

Transmission Limp Home Mode
Transmission function is monitored for abnormal condi-
tions. If a condition is detected that could result in
transmission damage, the transmission limp home mode
will be engaged. In this mode, the transmission will
remain in the current gear (3.7L engine) or in direct gear
(4.7L and 5.7L engines) until the vehicle is brought to a
stop.
To reset the transmission, use the following procedure:
1. Stop the vehicle.
2. Move the shift lever to the P (Park) position.
3. Turn off the engine, be sure to turn the key to the
LOCK position.
4. Wait approximately 10 seconds, then restart the en-
gine.
5. Move the shift lever to the desired gear range.If the problem is no longer detected, the transmission will
return to normal operation. If the problem persists, P
(Park), R (Reverse), and N (Neutral) will continue to
operate. Only 2nd gear (3.7L engine) or 3rd gear (4.7L
and 5.7L engines) will be available in the D (Drive)
position. Have the transmission checked at your autho-
rized dealer as soon as possible.
Torque Converter Clutch
A feature, designed to improve fuel economy, has been
included in the automatic transmission on your vehicle.
A clutch within the torque converter engages automati-
cally at a calibrated speed at light throttle. It engages at
higher speeds under heavier acceleration. This may re-
sult in a slightly different feeling or response during
normal operation in high gear. When the vehicle speed
drops below a calibrated speed, or during acceleration,
the clutch automatically and smoothly disengages. The
feature is operational in Overdrive and in Drive.
260 STARTING AND OPERATING

NOTE:The torque converter clutch will not engage
until the transmission fluid and engine coolant are warm
[usually after 1-3 miles (1.6 - 4.8 km) of driving]. Because
the engine speed is higher when the torque converter
clutch is not engaged, it may seem as if the transmission
is not shifting into Overdrive when cold. This is normal.
Manually shifting (using the ERS shift control) between 4
(direct gear) and 5/D (Overdrive gear) positions will
demonstrate that the transmission is able to shift into and
out of Overdrive.
NOTE:If the vehicle has not been driven in several
days, the first few seconds of operation after shifting the
transmission into gear may seem sluggish. This is due to
the fluid partially draining from the torque converter into
the transmission. This condition is normal and will not
cause damage to the transmission. The torque converter
will refill within five seconds of shifting from Park into
any other gear position.Rocking the Vehicle
If the vehicle becomes stuck in snow, sand, or mud, it can
often be moved by a rocking motion. Move the gear
selector rhythmically between D (Drive) and R (Reverse),
while applying slight pressure to the accelerator.
NOTE:The Electronic Stability Program (ESP) and
Traction Control (if equipped) should be turned OFF
before attempting to rock the vehicle. Refer to “Electronic
Brake Control System” in Section 3 of this manual.
The least amount of accelerator pedal pressure to main-
tain the rocking motion without spinning the wheels or
racing the engine is most effective. Racing the engine or
spinning the wheels, due to the frustration of not freeing
the vehicle, may lead to transmission overheating and
failure. Allow the engine to idle with the transmission
selector in N (Neutral) for at least one minute after every
STARTING AND OPERATING 261
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five rocking-motion cycles. This will minimize overheat-
ing and reduce the risk of transmission failure during
prolonged efforts to free a stuck vehicle.
CAUTION!
When “rocking” a stuck vehicle by moving between
“First” and R (Reverse), do not spin the wheels faster
than 15 mph (24 km/h), or drivetrain damage may
result.
FOUR-WHEEL DRIVE OPERATION
Quadra-Trac IOperating
Instructions/Precautions — If Equipped
The Quadra-Trac Iis a single speed (HI range only)
transfer case which provides convenient full-time
4–wheel drive. No driver interaction is required. This
transfer case divides engine torque almost evenly with 48percent of engine torque to the front axle and 52 percent
of engine torque to the rear axle. The Brake Traction
Control System (BTC), which combines standard ABS
and Traction Control, provides resistance to any wheel
that is slipping to allow additional torque transfer to
wheels with traction.
NOTE:The Quadra-Trac Isystem is not appropriate
for conditions where LOW range is recommended. Refer
to “Off-Road Driving Tips” in this section.
Quadra-Trac IIOperating
Instructions/Precautions — If Equipped
The Quadra-Trac IItransfer case is fully automatic in the
normal driving 4 HI mode. The Quadra-Trac IItransfer
case provides three mode positions — four wheel drive
high range, neutral, and four wheel drive low range.
This transfer case is fully automatic in the 4 HI mode.
This transfer case divides engine torque almost evenly
with 48 percent of engine torque to the front axle and 52
262 STARTING AND OPERATING

percent of engine torque to the rear axle. When speed
differences are increased between the front and rear drive
shafts, the transfer case can transmit up to 100 percent of
available engine torque to the front or rear drive shafts.
When additional traction is required, the 4 LOW position
can be used to lock the front and rear driveshafts together
and force the front and rear wheels to rotate at the same
speed. The 4 LOW position is intended for loose, slippery
road surfaces only. Driving in the 4 LOW position on dry
hard surfaced roads may cause increased tire wear and
damage to driveline components.
When operating your vehicle in 4 LOW, the engine speed
is approximately three times that of the 4 HI position at a
given road speed. Take care not to overspeed the engine
and do not exceed 25 mph (40 km/h).Proper operation of four wheel drive vehicles depends on
tires of equal size, type, and circumference on each
wheel. Any difference will adversely affect shifting and
cause damage to the transfer case.
Because four wheel drive provides improved traction,
there is a tendency to exceed safe turning and stopping
speeds. Do not go faster than road conditions permit.
STARTING AND OPERATING 263
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5. Repeat Steps 1– 4 to shift out of Neutral.
NOTE:If shift conditions/interlocks are not met, a
“CHECK SHIFT PROCEDURES” message will flash from
the EVIC (Electronic Vehicle Information Center). Referto “Electronic Vehicle Information Center (EVIC)” in
Section 4 of this manual. (See page 183 for more
information.)
Quadra-Drive IISystem — If Equipped
The optional Quadra-Drive IISystem features three
torque transfer couplings. The couplings include ELSD
(Electronic Limited Slip Differential) front and rear axles
and Quadra-Trac IItransfer case. The optional ELSD
axles are fully automatic and require no driver input to
operate. Under normal driving conditions the units func-
tion as standard axles balancing torque evenly between
left and right wheels. With a traction difference between
left and right wheels the coupling will sense a speed
difference. As one wheel begins to spin faster than the
other, torque will automatically transfer from the wheel
that has less traction to the wheel that has traction. While
the transfer case and axle couplings differ in design, their
Neutral Switch
STARTING AND OPERATING 267
5

Remember, never drive diagonally across a hill-always
drive straight up or down.
If the wheels start to slip as you approach the crest of a
hill, ease off the accelerator and maintain headway by
turning the front wheels slowly. This may provide a fresh
“bite” into the surface and will usually provide traction
to complete the climb.
Traction Downhill
Shift the transmission into a low gear and the transfer
case to 4WD LOW range. Let the vehicle go slowly down
the hill with all four wheels turning against engine
compression drag. This will permit you to control the
vehicle speed and direction.
When descending mountains or hills, repeated braking
can cause brake fade with loss of braking control. Avoid
repeated heavy braking by downshifting the transmis-
sion whenever possible.
After Driving Off-Road
Off-road operation puts more stress on your vehicle than
does most on-road driving. After going off-road it is
always a good idea to check for damage. That way you
can get any problems taken care of right away and have
your vehicle ready when you need it.
•Completely inspect the underbody of your vehicle.
Check tires, body structure, steering, suspension, and
exhaust system for damage.
•Check threaded fasteners for looseness, particularly on
the chassis, drivetrain components, steering, and sus-
pension. Retighten them, if required, and torque to the
values specified in the Service Manual.
•Check for accumulations of plants or brush. These
things could be a fire hazard. They might hide damage
to fuel lines, brake hoses, axle pinion seals, and
propeller shafts.
STARTING AND OPERATING 271
5

nuts until each nut has been tightened twice. Correct
wheel nut tightness is 130 N·m (95 ft. lbs). If in doubt
about the correct tightness, have them checked with a
torque wrench by your authorized dealer or at a service
station.
10. Lower the jack to it’s fully closed position.
WARNING!
A loose tire or jack, thrown forward in a collision or
hard stop could endanger the occupants of the ve-
hicle. Always stow the jack parts and the spare tire in
the places provided.
11. Secure the tire, jack, and tools in their proper loca-
tions.NOTE:Tire should be stowed with the “beauty” side
up. Storing the tire upside down may result in scratching
or damage to the wheel face. Continue winching up the
tire until you hear the winch “ratchet” three times.
Double check to ensure the tire is snug against the
underbody of the vehicle. Damage to the winch cable
may result if the vehicle is driven with the tire loose.
WARNING!
Do not use power tools to winch the tire up or down.
Impact type tools may damage the winch mecha-
nism.
12. Reinstall the plastic plug into the floor of the cargo
area.
WHAT TO DO IN EMERGENCIES 345
6

CAUTION!
Do not allow a petroleum-base fluid to contaminate
the brake fluid. Seal damage may result.
Front/Rear Axle Fluid
Front Axle Fluid Level Check
Lubricant should be to the bottom of the oil fill hole.
Rear Axle Fluid Level Check
Lubricant should be 1/2” (1 cm) below the oil fill hole.
Adding Fluid
Add lubricant only at the fill hole and only to the level
specified above.
Selection of Lubricant
Use only manufacturer’s recommended fluid, refer to
Fluids, Lubricants, and Genuine Parts for correct fluid
type.
Transfer Case
Fluid Level Check
Inspect the transfer case for fluid leaks. If a fluid leak is
found, the transfer case fluid level can be checked by
removing the filler plug located on the back side of the
transfer case. The fluid level should be at the bottom edge
of the filler plug hole when the vehicle is in a level
position.
Adding Fluid
Add fluid at the filler hole until it runs out of the hole
when the vehicle is in a level position.
Drain
First remove fill plug, then remove drain plug. Recom-
mended tightening torque for drain and fill plugs is
15–25 ft. lbs (20–34 N·m).
MAINTAINING YOUR VEHICLE 385
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