2008 JEEP GRAND CHEROKEE transmission

The transmission will downshift from Overdrive to the
most desirable gear if the accelerator pedal is fully
depressed at vehicle speeds above approximately 35 mph
(56 km/h).
When To Use ªTOW/HAULº Mode Ð If Equipped
When driving in hilly areas, towing a trailer, carrying a
heavy load, etc., and frequent transmission shifting oc-
curs, press the ªTOW/HAULº switch. This will improve
performance and reduce the potential for transmission
overheating or failure due to excessive shifting. When
operating in ªTOW/HAULº mode, the transmission will
shift to direct gear and Overdrive will be enabled under
steady cruise conditions.
The ªTOW/HAULº light will illuminate in the instru-
ment cluster to indicate when the switch has been
activated. Pressing the switch a second time restores
normal operation. If the ªTOW/HAULº mode is desired,
the switch must be pressed each time the engine is
started.
TOW/HAUL Switch
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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.
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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 ªElectronic
Brake Control Systemº 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
292 STARTING AND OPERATING

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 ªrockingº a stuck vehicle by moving between
ªFirstº 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 ITOperating
Instructions/Precautions Ð If Equipped
The Quadra-Trac Itis 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 Itsystem is not appropriate
for conditions where LOW range is recommended. Refer
to ªOff-Road Driving Tipsº in this section.
Quadra-Trac IITOperating
Instructions/Precautions Ð If Equipped
The Quadra-Trac IIttransfer case is fully automatic in the
normal driving 4 HI mode. The Quadra-Trac IIttransfer
case provides three mode positions Ð 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
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WARNING!
You or others could be injured if you leave the
vehicle unattended with the transfer case in the N
(Neutral) position without first fully engaging the
parking brake. The transfer case N (Neutral) position
disengages both the front and rear driveshafts from
the powertrain and will allow the vehicle to move
regardless of the transmission position. The parking
brake should always be applied when the driver is
not in the vehicle.
Shift Positions
For additional information on the appropriate use of each
transfer case mode position, see the information below:
4HI
Four Wheel Drive High Range Ð All roads surfaces such
as ice, snow, gravel, sand, and dry hard pavement.
N (Neutral)
Neutral Ð Disengages both the front and rear driveshafts
from the powertrain. To be used for flat towing behind
another vehicle. Refer to ªRecreational Towingº in Sec-
tion 5 of this manual.
4 LOW
Four Wheel Drive Low Range Ð Low speed 4 wheel
drive. Locks the front and rear driveshafts together.
Forces the front and rear wheels to rotate at the same
speed. Additional traction and maximum pulling power
for loose, slippery road surfaces only. Do not exceed 25
mph (40 km/h).
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Shifting Procedures
4HIto4LOW
With the vehicle at speeds of 0 to 3 mph (0 to 5 km/h),
key ON or engine running, shift the transmission into N
(Neutral), and raise the transfer case T-handle. ªThe 4WD
LOW Indicator Lampº in the instrument cluster will
begin to flash and remain on solid when the shift is
complete. Release the T-handle.
NOTE:If shift conditions/interlocks are not met, or a
transfer case motor temperature protection condition
exists, a ªCHECK SHIFT PROCEDURESº message will
flash from the EVIC (Electronic Vehicle Information Cen-
ter). Refer to ªElectronic Vehicle Information Center
(EVIC)º in Section 4 of this manual.
Shifter T-Handle
296 STARTING AND OPERATING

4 LOW to 4 HI
With the vehicle at speeds of 0 to 3 mph (0 to 5 km/h),
key ON or engine running, shift the transmission into N
(Neutral), and raise the transfer case T-handle. The ª4WD
LOW Indicator Lampº in the instrument cluster will flash
and go out when the shift is complete. Release the
T-handle.
NOTE:If shift conditions/interlocks are not met, or a
transfer case motor temperature protection condition
exists, a ªCHECK SHIFT PROCEDURESº message will
flash from the EVIC (Electronic Vehicle Information Cen-
ter). Refer to ªElectronic Vehicle Information Center
(EVIC)º in Section 4 of this manual.NOTE:Shifting into or out of 4WD LOW is possible
with the vehicle completely stopped, however difficulty
may occur due to the mating clutch teeth not being
properly aligned. Several attempts may be required for
clutch teeth alignment and shift completion to occur. The
preferred method is with the vehicle rolling 0 to 3 mph (0
to 5 km/h). If the vehicle is moving faster than 3 mph (5
km/h), the transfer case will not allow the shift.
Neutral (N) Shift Procedure
1. Key ON, engine off.
2. Vehicle stopped, with foot on brake.
3. Place transmission in N (Neutral).
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and/or the flow rate is reduced. If you must cross
flowing water avoid depths in excess of 9 inches. The
flowing water can erode the streambed causing your
vehicle to sink into deeper water. Determine exit point(s)
that are downstream of your entry point to allow for
drifting.
Standing Water
Avoid driving in standing water deeper than 20 inches,
and reduce speed appropriately to minimize wave ef-
fects. Maximum speed in 20 inches of water is less than 5
mph (8 km/h).
Maintenance
After driving through deep water, inspect your vehicle
fluids and lubricants (engine oil, transmission oil, axle,
transfer case) to assure the fluids have not been contami-
nated. Contaminated fluid (milky, foamy in appearance)
should be flushed/changed as soon as possible to pre-
vent component damage.Driving In Snow, Mud and Sand
In heavy snow, when pulling a load, or for additional
control at slower speeds, shift the transmission to a low
gear and shift the transfer case to 4WD LOW if necessary.
Refer to ªFour-Wheel Drive Operationº in this section.
Do not shift to a lower gear than necessary to maintain
forward motion. Over-revving the engine can spin the
wheels and traction will be lost.
Avoid abrupt downshifts on icy or slippery roads, be-
cause engine braking may cause skidding and loss of
control.
Hill Climbing
NOTE:Before attempting to climb a hill, determine the
conditions at the crest and/or on the other side.
Before climbing a steep hill,shift the transmission to a
lower gear and shift the transfer case to 4WD LOW. Use
first gear and 4WD LOW for very steep hills.
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