2006 JEEP GRAND CHEROKEE air condition

Tire Pressures for High Speed Operation
The manufacturer advocates driving at safe speeds
within posted speed limits. Where speed limits or condi-
tions are such that the vehicle can be driven at high
speeds, maintaining correct tire inflation pressure is very
important. Increased tire pressure and reduced vehicle
loading may be required for high speed vehicle opera-
tion. Refer to original equipment or an authorized tire
dealer for recommended safe operating speeds, loading
and cold tire inflation pressures.
WARNING!
High speed driving with your vehicle under maxi-
mum load is dangerous. The added strain on your
tires could cause them to fail. You could have a
serious accident. Don’t drive a vehicle loaded to the
maximum capacity at continuous speeds above 75
mph (120 km/h).
Radial-Ply Tires
WARNING!
Combining radial ply tires with other types of tires
on your vehicle will cause your vehicle to handle
poorly. The instability could cause an accident. Al-
ways use radial tires in sets of four. Never combine
them with other types of tires.
Cuts and punctures in radial tires are repairable only in
the tread area because of sidewall flexing. Consult your
dealer for radial tire repairs.
Tire Spinning
When stuck in mud, sand, snow, or ice conditions, do not
spin your vehicle’s wheels above 35 mph (55 km/h).
290 STARTING AND OPERATING

MMT In Gasoline
MMT is a manganese containing metallic additive that is
blended into some gasoline to increase octane. Gasoline
blended with MMT provides no performance advantage
beyond gasoline of the same octane number without
MMT. Gasoline blended with MMT reduces spark plug
life and reduces emission system performance in some
vehicles. The manufacturer recommends that gasoline
without MMT be used in your vehicle. The MMT content
of gasoline may not be indicated on the gasoline pump,
therefore, you should ask your gasoline retailer whether
or not his/her gasoline contains MMT.
It is even more important to look for gasoline without
MMT in Canada because MMT can be used at levels
higher than allowed in the United States. MMT is pro-
hibited in Federal and California reformulated gasoline.
Materials Added To Fuel
All gasoline sold in the United States is required to
contain effective detergent additives. Use of additional
detergents or other additives is not needed under normal
conditions.
Fuel System Cautions
CAUTION!
Follow these guidelines to maintain your vehicle’s
performance:
•The use of leaded gas is prohibited by Federal law.
Using leaded gasoline can impair engine performance,
damage the emission control system.
304 STARTING AND OPERATING

•Guard against carbon monoxide with proper mainte-
nance. Have the exhaust system inspected every time
the vehicle is raised. Have any abnormal conditions
repaired promptly. Until repaired, drive with all side
windows fully open.
•Keep the liftgate closed when driving your vehicle to
prevent carbon monoxide and other poisonous ex-
haust gases from entering the vehicle.
FUEL TANK FILLER CAP (GAS CAP)
The fuel cap is located on the left side of the vehicle. If the
fuel cap is lost or damaged, be sure the replacement cap
is for use with this vehicle.
Fuel Filler Cap Location
306 STARTING AND OPERATING

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.
Air Conditioning
Turn off temporarily.
refer to Cooling System Operating information in the
Maintenance section of this manual for more informa-
tion.
RECREATIONAL TOWING (BEHIND
MOTORHOME, ETC.)
Towing–2WD Models
Recreational towing is allowed ONLY if the driveshaft
is removed.Towing with the rear wheels on the ground
while the driveshaft is connected can result in severe
transmission damage.
Towing—Quadra-Trac I (Single-Speed Transfer
Case) 4WD Models
Recreational towing is not allowed.This model does not
have a N (Neutral) position in the transfer case.
320 STARTING AND OPERATING

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
removes this heat. You can also turn the Temperature
Control to maximum heat, the Mode Control to floor, and
the Fan Control to High. This allows the heater core to act
as a supplement to the radiator and aids in removing heat
from the engine cooling system.
CAUTION!
Driving with a hot cooling system could damage
your vehicle. If the temperature gauge reads“H”,
pull over and stop the vehicle. Idle the vehicle with
the air conditioner turned off until the pointer drops
back into the normal range. If the pointer remains on
the“H”, and you hear continuous chimes, turn the
engine off immediately, and call for service.
WHAT TO DO IN EMERGENCIES 329
6

MAINTAINING YOUR VEHICLE
CONTENTS

3.7L Engine...........................344

4.7L Engine...........................345

5.7L Engine...........................346

Onboard Diagnostic System—OBDII........347
▫Loose Fuel Filler Cap Message............347

Emissions Inspection And Maintenance
Programs............................348

Replacement Parts......................349

Dealer Service.........................350
Maintenance Procedures..................350
▫Engine Oil..........................351
▫Drive Belts—Check Condition And
Tensioner...........................354
▫Spark Plugs.........................355
▫Catalytic Converter....................355
▫Crankcase Emission Control System........357
▫Air Cleaner Filter.....................358
▫Maintenance-Free Battery................358
7

▫Air Conditioner Maintenance.............359
▫Power Steering Fluid Check..............360
▫Body Lubrication.....................362
▫Windshield Wiper Blades................362
▫Windshield Washers—Front And Rear.....362
▫Exhaust System......................363
▫Cooling System.......................364
▫Hoses And Vacuum/Vapor Harnesses.......369
▫Brake System........................369
▫Automatic Transmission................371
▫Transfer Case........................374
▫Front/Rear Axle Fluid..................375▫Appearance Care And Protection From
Corrosion...........................376

Fuse Panel...........................380
▫Interior Fuses........................380
▫Underhood Fuses
(Power Distribution Center)..............382
▫Underhood Fuses
(Integrated Power Module)..............384

Vehicle Storage........................385

Replacement Bulbs......................386

Bulb Replacement......................387
▫Head Light..........................387
▫Front Turn Signal.....................388
▫Front Fog Light......................389
342 MAINTAINING YOUR VEHICLE

Materials Added to Engine Oils
The manufacturerstrongly recommendsagainst the ad-
dition of any additives (other than leak detection dyes) to
engine oil. Engine oil is an engineered product and it’s
performance may be impaired by supplemental addi-
tives.
Disposing of Used Engine Oil
Care should be taken in disposing of the used engine oil
from your vehicle. Used oil, indiscriminately discarded,
can present a problem to the environment. Contact your
local authorized dealer, service station, or governmental
agency for advice on how and where used oil can be
safely discarded in your area.
Engine Oil Filter
The engine oil filter should be replaced with a new filter
at every oil change.
Engine Oil Filter Selection
All of the manufacturer’s engines have a full-flow type
disposable oil filter. Use a filter of this type for replace-
ment. The quality of replacement filters varies consider-
ably. Only high quality filters should be used to assure
most efficient service. Moparengine oil filters are high
quality oil filters and are recommended.
Drive Belts—Check Condition and Tensioner
Belt tension is controlled by means of an automatic
tensioner. No belt tension adjustments are required.
However, belt and belt tensioner condition should be
inspected at the specified intervals, and replaced if re-
quired. See your authorized dealer for service.
At the mileage indicated in the maintenance schedule, all
belts and tensioner should be checked for condition.
Improper belt tension can cause belt slippage and failure.
354 MAINTAINING YOUR VEHICLE