2012 JEEP GRAND CHEROKEE clutch

DRIVE
This range should be used for most city and highway
driving. It provides the smoothest upshifts and down-
shifts, and the best fuel economy. The transmission
automatically upshifts through underdrive first and sec-
ond gears, direct third gear and overdrive fourth and
fifth gears. The DRIVE position provides optimum driv-
ing characteristics under all normal operating conditions.
To access all six available gears, you must use the
Electronic Range Select (ERS) feature (refer to “Electronic
Range Select (ERS)” in this section).
When frequent transmission shifting occurs (such as
when operating the vehicle under heavy loading condi-
tions, in hilly terrain, traveling into strong head winds, or
while towing heavy trailers), use the Electronic Range
Select (ERS) feature (refer to “Electronic Range Select
(ERS)” in this section) to select a lower gear range. Underthese conditions, using a lower gear range will improve
performance and extend transmission life by reducing
excessive shifting and heat buildup.
If the transmission operating temperature exceeds nor-
mal operating limits, the powertrain controller will
modify the transmission shift schedule and expand the
range of torque converter clutch engagement. This is
done to prevent transmission damage due to overheat-
ing.
If the transmission becomes extremely hot, the “Trans-
mission Temperature Warning Light” may illuminate and
the transmission may downshift out of Overdrive until
the transmission cools down.
NOTE:
Use caution when operating a heavily loaded
vehicle at low speeds (such as towing a trailer up a steep
grade, or in stop-and-go traffic) during hot weather. In
these conditions, torque converter slip can impose a
significant additional heat load on the cooling system.
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Downshifting the transmission to the lowest possible
gear (when climbing a grade), or shifting to NEUTRAL
(when stopped in heavy traffic) can help to reduce this
excess heat generation.
During cold temperatures, transmission operation may
be modified depending on engine and transmission
temperature as well as vehicle speed. This feature im-
proves warm up time of the engine and transmission to
achieve maximum efficiency. Engagement of both the
torque converter clutch and the top overdrive gear are
inhibited until the transmission fluid is warm (refer to the
“Note” under “Torque Converter Clutch” in this section).
During extremely cold temperatures (-16°F [-27°C] or
below), operation may briefly be limited to first and
direct gears only. Normal operation will resume once the
transmission temperature has risen to a suitable level.Transmission Limp Home Mode
Transmission function is monitored electronically for
abnormal conditions. If a condition is detected that could
result in transmission damage, Transmission Limp Home
Mode is activated. In this mode, the transmission remains
in third gear regardless of which forward gear is selected.
PARK, REVERSE, and NEUTRAL will continue to oper-
ate. The Malfunction Indicator Light (MIL) may be illu-
minated. Limp Home Mode allows the vehicle to be
driven to an authorized dealer for service without dam-
aging the transmission.
In the event of a momentary problem, the transmission
can be reset to regain all forward gears by performing the
following steps:
1. Stop the vehicle.
2. Shift the transmission into PARK.
3. Turn the ignition switch to the LOCK/OFF position.
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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 calibrated speeds. This may result in a slightly
different feeling or response during normal operation in
the upper gears. When the vehicle speed drops or during
some accelerations, the clutch automatically disengages.
NOTE:
•The torque converter clutch will not engage, and the
transmission will not shift into the top overdrive gear,
until the transmission fluid and engine coolant are
warm [usually after 1 to 3 miles (1.6 to 4.8 km) of
driving]. Because top gear is disabled, and engine
speed is higher when the torque converter clutch is not
engaged, it may seem as if the transmission is not
shifting properly when cold. This is normal. Using theElectronic Range Select (ERS) feature, when the trans-
mission is sufficiently warm, will demonstrate that the
transmission is able to shift into and out of Overdrive.
•If the vehicle has not been driven for several days, the
first few seconds of operation after shifting the trans-
mission 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 con-
verter will refill within five seconds after starting the
engine.
FOUR-WHEEL DRIVE OPERATION
Quadra-Trac I
Operating Instructions/
Precautions – If Equipped
The Quadra-Trac I is a single-speed (HI range only)
transfer case, which provides convenient full-time four-
wheel drive. No driver interaction is required. The Brake
Traction Control (BTC) System, which combines standard
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4WD LOW To 4WD HI
With the vehicle at speeds of 0 to 3 mph (0 to 5 km/h), the
ignition switch in the ON position or the engine running,
shift the transmission into NEUTRAL, and press the
“4WD LOW” button once on the transfer case switch. The
“4WD LOW” indicator light in the instrument cluster
will flash and go out when the shift is complete.
NOTE:
•If shift conditions/interlocks are not met, or a transfer
case motor temperature protection condition exists, a
“For 4x4 High Slow Below 3 MPH or 5 KPH Put Trans
in N Press 4 Low” message will flash from the
Electronic Vehicle Information Center (EVIC). Refer to
“Electronic Vehicle Information Center (EVIC)” in
“Understanding Your Instrument Panel” for further
information.
•Shifting into or out of 4WD LOW is possible with the
vehicle completely stopped; however, difficulty mayoccur due to the mating clutch teeth not being prop-
erly 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 Shift Procedure
1. Turn the ignition switch to the ON position, engine off.
2. Vehicle stopped, with foot on brake.
3. Place the transmission into NEUTRAL.
4. Hold down the NEUTRAL “pin” switch (with a pen,
etc.) for four seconds until the LED light by the switch
starts to blink indicating shift in progress. The light will
stop blinking (stay on solid) when the NEUTRAL shift is
complete.
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