2005 JEEP GRAND CHEROKEE Engine

After Starting
The idle speed will automatically decrease as the engine
warms up.
CAUTION!
Long periods of engine idling, especially at high
engine speeds can cause excessive exhaust tempera-
tures which can damage your vehicle. Do not leave
your vehicle unattended with the engine running.
ENGINE BLOCK HEATER — IF EQUIPPED
The engine block heater warms engine coolant and
permits quicker starts in cold weather. Connect the cord
to a standard 110-115 volt AC electrical outlet with
grounded, three wire extension cord.
Use the heater when temperatures below 0°F (-18°C) are
expected to last for several days.The engine block heater cord is located:
•3.7L/4.7L Engine — coiled and strapped to the engine
oil dipstick tube.
•5.7L Engine — bundled and fastened to the injector
harness.
WARNING!
Remember to disconnect the cord before driving.
Damage to the 110-115 volt AC electrical cord could
cause electrocution.
232 STARTING AND OPERATING

WARNING!
It is dangerous to shift the selector lever out of P
(Park) or N (Neutral) if the engine speed is higher
than idle speed. If your foot is not firmly on the
brake pedal, the vehicle could accelerate quickly
forward or in reverse. You could lose control of the
vehicle and hit someone or something. Only shift
into gear when the engine is idling normally and
when your foot is firmly on the brake pedal.
Brake Transmission Shift Interlock System
This vehicle is equipped with a brake transmission shift
interlock system (BTSI) that holds the gearshift lever in
the P (Park) position when the ignition switch is in the
LOCK position. To move the gear selector lever out of the
P (Park) position, the ignition switch must be turned to
the ON position, and the brake pedal must be depressed.
Gear Ranges
P (Park)
Supplements the parking brake by locking the transmis-
sion. The engine can be started in this range. Never use P
(Park) while the vehicle is in motion. Apply the parking
brake when leaving the vehicle in this range.
WARNING!
Unintended movement of a vehicle could injure those
in and near the vehicle. As with all vehicles, you
should never exit a vehicle while the engine is running.
Before exiting a vehicle, you should apply the park
brake, shift the transmission into P (Park), and remove
the key from the ignition. Once the key is removed
from the ignition the transmission shift lever is locked
in the P (Park) position, securing the vehicle against
unwanted movement. Furthermore, you should never
leave children unattended inside a vehicle.
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R (Reverse)
Shift into this range only after the vehicle has come to a
complete stop.
N (Neutral)
No power is transmitted from the engine to the drive
axle. When the brakes are released, the vehicle can roll
freely. Do not engage in N (Neutral) position while
driving except to coast when the vehicle is in danger of
skidding (e.g., on icy roads).
NOTE:Towing the vehicle, coasting, or driving for any
other reason with selector lever in N (Neutral) can result
in severe transmission damage. Refer to “Recreational
Towing” in Section 5 and “Towing a Disabled Vehicle” in
Section 6 of this manual.
D (Drive)
The transmission automatically upshifts through fifth
gear. The D (Drive) position provides optimum driving
characteristics under all normal operating conditions.
Electronic Range Select (ERS)Operation
The Electronic Range Select (ERS) shift control allows
you to move the shifter left (-) or right (+) when the
shifter is in the D (Drive) position, allowing the selection
of the desired top gear. For example, if the driver shifts
the transmission into 3 (third gear), the transmission will
never shift above third gear, but can shift down to 2
(second) or 1 (first), when needed.
WARNING!
Do not downshift for additional engine braking on a
slippery surface. The drive wheels could lose their
grip and the vehicle could skid.
Screen Display12 34D
Actual Gear(s) Allowed 1 1-2 1-3 1-4 1-5
NOTE:To select the proper gear position for maximum
deceleration (engine braking), move the shift lever to the
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5

left “D(-)” and hold it there. The transmission will shift to
the range from which the vehicle can best be slowed
down.
Overdrive Operation
The overdrive automatic transmission contains an elec-
tronically controlled fourth and fifth speed (Overdrive).
The transmission will automatically shift from 3rd 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 Overdrive
and 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.
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 cooldown, the transmission will
resume normal operation.
In high ambient temperatures with sustained high engine
speed and load, an upshift followed shortly thereafter by
236 STARTING AND OPERATING

a downshift may occur. This is a normal part of the
overheat protection strategy when operating in the
“Tow/Haul” mode.
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 “TOW/HAUL” Mode — If Equipped
When driving in hilly areas, towing a trailer, carrying a
heavy load, etc., and frequent transmission shifting oc-
curs, press the “TOW/HAUL” button. This will improve
performance and reduce the potential for transmission
overheating or failure due to excessive shifting. When
operating in “TOW/HAUL” mode, the transmission will
shift to 3rd gear and 4th will be enabled under steady
cruise conditions.The “TOW/HAUL” 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 “TOW/HAUL” mode is desired,
the switch must be pressed each time the engine is
started.
Tow/Haul Button
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5

Torque Converter Clutch
A feature designed to improve fuel economy is included
in all automatic transmissions. A clutch within the torque
converter engages automatically at a calibrated speed at
light throttle. It engages at higher speeds under heavier
acceleration. This may result 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 Over-
drive and in Drive.
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 between 3 (third gear) and 4 (fourthgear) positions (using the ERS shift control) will demon-
strate 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.
238 STARTING AND OPERATING

NOTE:The Electronic Stability Program (ESP) and
Traction Control (if equipped) should be turned OFF
before attempting to rock the vehicle. Refer to 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
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 48
percent 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
STARTING AND OPERATING 239
5

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
percent of engine torque to the rear axle. When speed
differences are increased between the front and rear driveshafts, 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.
240 STARTING AND OPERATING