2007 JEEP GRAND CHEROKEE heating

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
5

Be sure the parking brake is firmly set when parked and
the gear shift lever is in the P (Park) position. When
parking on a hill, you should apply the parking brake
before placing the gear shift lever in P (Park), otherwise
the load on the transmission locking mechanism may
make it difficult to move the selector out of P (Park).
WARNING!
•Always fully apply the parking brake when leav-
ing your vehicle, or it may roll and cause damage
or injury. Also, be certain to leave the transmis-
sion in P (Park). Failure to do so may allow the
vehicle to roll and cause damage or injury.
•Leaving children in a vehicle unattended is dan-
gerous for a number of reasons. A child or others
could be injured. Children should be warned not
to touch the parking brake or the gear selector
lever. Don’t leave the keys in the ignition. A child
could operate power windows, other controls, or
move the vehicle.
•Be sure the parking brake is fully disengaged
before driving, failure to do so can lead to brake
problems due to excessive heating of the rear
brakes.
Parking Brake
STARTING AND OPERATING 273
5

Towing Tips — Automatic Transmission
The “D” range can be selected when towing. However, if
frequent shifting occurs while in this range, the ”Tow/
Haul” mode (if equipped) or a lower gear range should
be selected.
NOTE:Using the ”Tow/Haul” mode (if equipped) or a
lower gear range while operating the vehicle under
heavy operating conditions will improve performance
and extend transmission life by reducing excessive shift-
ing and heat build up. This action will also provide better
engine braking.
The automatic transmission fluid and filter should be
changed if you REGULARLY tow a trailer for more than
45 minutes of continuous operation. Refer to “Mainte-
nance Schedule B” in Section 8 of this manual for
transmission fluid change intervals.
NOTE:Check the automatic transmission fluid level
before towing.
Towing Tips — Electronic Speed Control (If
Equipped)

Don’t use in hilly terrain or with heavy loads.
When using the speed control, if you experience speed
drops greater than 10 mph (16 km/h), disengage until
you can get back to cruising speed.
Use speed control in flat terrain and with light loads to
maximize fuel efficiency.
Towing Tips — Cooling System
To reduce potential for engine and transmission over-
heating, take the following actions:
City Driving
When stopped for short periods of time, put transmission
in neutral and increase engine idle speed.
Highway Driving
Reduce speed.
STARTING AND OPERATING 331
5

HAZARD WARNING FLASHERS
Your vehicle’s hazard warning flasher is an emergency
warning system. When you activate it, all front and rear
directional signals will flash intermittently. Use it when your
vehicle is disabled on or near the road. It warns other drivers
to steer clear of you and your vehicle. This is an emergency
warning system, not to be used when the vehicle is in motion.
To activate the warning flasher, push down on the button
on top of the steering column until it latches. To turn the
warning flasher off, push down again to unlatch the
button.
NOTE:With extended use, the flasher may run down
your battery.
IF YOUR ENGINE OVERHEATS
In any of the following situations, you can reduce the
potential for overheating by taking the appropriate ac-
tion.
•On the highways — Slow down.
•In city traffic — While stopped, put transmission in N
(Neutral), but do not increase engine idle speed.
NOTE:There are steps that you can take to slow down
an impending overheat condition. If your air conditioner
is on, turn it off. The air conditioning system adds heat to
the engine cooling system and turning off the A/C
Hazard Warning Switch
338 WHAT TO DO IN EMERGENCIES

WARNING!
A hot exhaust system can start a fire if you park over
materials that can burn. Such materials might be
grass or leaves coming into contact with your ex-
haust system. Do not park or operate your vehicle in
areas where your exhaust system can contact any-
thing that can burn.
In unusual situations involving grossly malfunctioning
engine operation, a scorching odor may suggest severe
and abnormal catalyst overheating. If this occurs, stop
the vehicle, turn off the engine and allow it to cool.
Service, including a tune up to manufacturer’s specifica-
tions, should be obtained immediately.
To minimize the possibility of catalytic converter dam-
age:
•Do not shut off the engine or interrupt the ignition
when the transmission is in gear and the vehicle is in
motion.
•Do not try to start the engine by pushing or towing the
vehicle.
•Do not idle the engine with any spark plug wires
disconnected or removed, such as when diagnostic
testing, or for prolonged periods during very rough
idle or malfunctioning operating conditions.
Crankcase Emission Control System
Proper operation of this system depends on freedom
from sticking or plugging due to deposits. As vehicle
mileage builds up, the PCV valve and passages may
accumulate deposits. If a valve is not working properly,
replace it with a new valve. DO NOT ATTEMPT TO
CLEAN THE OLD PCV VALVE!
MAINTAINING YOUR VEHICLE 369
7

Electronic Vehicle Information
Center (EVIC).......................180,183
Emergency, In Case of
Freeing Vehicle When Stuck............... 261
Hazard Warning Flasher................. 338
Jacking............................. 339
Jump Starting......................... 346
Tow Hooks.......................... 349
Emission Control System Maintenance......359,412
Engine
Air Cleaner.......................... 367
Block Heater......................... 253
Break-In Recommendations................ 64
Compartment................354,355,356,357
Compartment Identification......354,355,356,357
Cooling ............................. 376
Exhaust Gas Caution.................. 65,309
Fails to Start.......................... 249
Fuel Requirements..................305,407Oil ..............................362,407
Oil Change Interval.................... 363
Oil Disposal.......................... 365
OilFilter ............................ 366
Oil Filter Disposal...................... 365
Oil Selection....................363,364,407
Oil Synthetic......................... 365
Overheating.......................... 338
Starting............................. 249
Temperature Gauge..................... 179
Engine Oil Viscosity...................364,365
Engine Oil Viscosity Chart..............364,365
Enhanced Accident Response Feature.......... 51
Entry System, Illuminated.................. 19
Event Data Recorder...................... 52
Exhaust Gas Caution................ 65,309,376
Exhaust System......................... 375
ExteriorFinishCare ...................... 390
456 INDEX

New Vehicle Break-In Period................ 64
Occupant Restraints....................... 34
Octane Rating, Gasoline (Fuel)............305,306
Odometer..........................180,181
Trip ................................ 180
Off-Pavement Driving (Off-Road)..........268,388
Off-Road Driving (Off-Pavement)..........268,388
Oil, Engine............................ 362
Capacity............................ 407
Change Interval....................... 363
Dipstick............................. 362
Disposal............................ 365
Filter ............................... 366
Filter Disposal........................ 365
Identification Logo..................... 364
Materials Added to..................... 365
Pressure Warning Light.................. 177
Recommendation.................363,364,407Synthetic............................ 365
Viscosity.......................364,365,407
Onboard Diagnostic System..............358,359
Opener, Garage Door (HomeLink) ........... 146
Outside Rearview Mirrors.................. 73
Overdrive............................. 258
Overdrive OFF Switch.................... 258
Overhead Console....................... 145
Overheating, Engine...................179,338
Owner’s Manual (Operator Manual).......... 448
PaintCare ............................. 389
Paint Damage.......................... 389
Panic Alarm............................ 22
Park Assist System, Rear.................. 138
Parking Brake.......................... 272
Passing Light........................... 118
Pedals, Adjustable....................... 124
Pets.................................. 64
INDEX 463
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