2006 JEEP GRAND CHEROKEE Owners Manual

ONLY the correct type thermostat. Other designs may
result in unsatisfactory cooling performance, poor gas
mileage, and increased emissions.
Hoses and Vacuum/Vapor Harnesses
Inspect surfaces of hoses and nylon tubing for evidence
of heat and mechanical damage. Hard or soft spots,
brittle rubber, cracking, tears, cuts, abrasions, and exces-
sive swelling indicate deterioration of the rubber.
Pay particular attention to the hoses nearest to high heat
sources such as the exhaust manifold. Inspect hose rout-
ing to be sure hoses do not touch any heat source or
moving component that may cause heat damage or
mechanical wear.
Insure nylon tubing in these areas has not melted or
collapsed. Inspect all hose connections such as clamps
and couplings to make sure they are secure and no leaksare present. Components should be replaced immedi-
ately if there is any evidence of degradation that could
cause failure.
Brake System
In order to assure brake system performance, all brake
system components should be inspected periodically.
Refer to the appropriate“Maintenance Schedule”in
Section 8 for suggested service intervals.
WARNING!
Riding the brakes can lead to brake failure and
possibly an accident. Driving with your foot resting
or riding on the brake pedal can result in abnormally
high brake temperatures, excessive lining wear, and
possible brake damage. You wouldn’t have your full
braking capacity in an emergency.
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Brake and Power Steering System Hoses
When servicing the vehicle for scheduled maintenance,
inspect surface of hoses for evidence of heat and me-
chanical damage. Hard and brittle rubber, cracking, tears,
cuts, abrasion, and excessive swelling suggest deteriora-
tion of the rubber. Particular attention should be made to
examining those hose surfaces nearest to high heat
sources, such as the exhaust manifold.
Inspect all hose clamps and couplings to make sure they
are secure and no leaks are present.
NOTE:Often fluids such as oil, power steering fluid,
and brake fluid are used during assembly plant opera-
tions to ease the assembly of hoses to couplings. There-
fore, oil wetness at the hose-coupling area is not neces-
sarily an indication of leakage. Actual dripping of hot
fluid when systems are under pressure (during vehicle
operation) should be noted before hose is replaced based
on leakage.NOTE:Inspection of brake hoses should be done when-
ever the brake system is serviced and every engine oil
change.
WARNING!
Worn brake hoses can burst and cause brake failure.
You could have an accident. If you see any signs of
cracking, scuffing, or worn spots, have the brake
hoses replaced immediately.
Brake Master Cylinder
The fluid level in the master cylinder should be checked
when performing under hood services, or immediately if
the brake system warning lamp shows system failure
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Be sure to clean the top of the master cylinder area before
removing the cap. If necessary, add fluid to bring the
fluid level up to the requirements described on the brake
fluid reservoir. With disc brakes, fluid level can be
expected to fall as the brake pads wear. However, low
fluid level may be caused by a leak and a checkup may be
needed.
Use only manufacturer’s recommended brake fluid, refer
to Fluids, Lubricants, and Genuine Parts for correct fluid
type.
WARNING!
Use of a brake fluid that may have a lower initial
boiling point or unidentified as to specification, may
result in sudden brake failure during hard pro-
longed braking. You could have an accident.
WARNING!
Overfilling the brake fluid reservoir can result in
spilling brake fluid on hot engine parts and the
brake fluid catching fire.
Use only brake fluid that has been in a tightly closed
container to avoid contamination from foreign matter. Do
not allow petroleum base fluid to contaminate the brake
fluid as seal damage will result.
Automatic Transmission
Selection of Lubricant
It is important that the proper lubricant is used in the
transmission to assure optimum transmission perfor-
mance. Use only manufacturer’s recommended transmis-
sion fluid, refer to Fluids, Lubricants, and Genuine Parts
for correct fluid type. It is important that the transmission
fluid be maintained at the prescribed level using the
recommended fluid.
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7

CAUTION!
Using a transmission fluid other than the manufac-
turer’s recommended fluid may cause deterioration
in transmission shift quality and/or torque converter
shudder. Using a transmission fluid other than the
manufacturer’s recommended fluid will result in
more frequent fluid and filter changes. Refer to
Fluids, Lubricants, and Genuine Parts for correct
fluid type.
Fluid Level Check
NOTE:If equipped with a dipstick, use the following
procedure. If your vehicle has a capped dipstick tube, it
is sealed and should not be tampered with. Your autho-
rized dealer has the proper tools to ensure that the fluid
level is set properly.Check the fluid level while the transmission is at normal
operating temperature. This occurs after at least 15 miles
(25 km) of driving. At normal operating temperature the
fluid cannot be held comfortably between the fingertips.
To check the automatic transmission fluid level properly,
the following procedure must be used:
1. Operate the engine at idle speed and normal operating
temperature.
2. The vehicle must be on level ground.
3. Fully apply the parking brake and press the brake
pedal.
4. Place the gear selector momentarily in each gear
position ending with the lever in P (Park).
5. Remove the dipstick, wipe it clean and reinsert it until
seated.
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6. Remove the dipstick again and note the fluid level on
both sides. The fluid level should be between the“HOT”
(upper) reference holes on the dipstick at normal operat-
ing temperature. The fluid level is only valid if there is a
solid coating of oil is seen on both sides of the dipstick. If
the fluid is low, add as required into the dipstick tube.Do
not overfill.After adding any quantity of oil through the
oil fill tube, wait a minimum of two (2) minutes for the oil
to fully drain into the transmission before rechecking the
fluid level.
NOTE:If it is necessary to check the transmissionbelow
the operating temperature, the fluid level should be
between the two“COLD”(lower) holes on the dipstick
with the fluid at approximately 70°F (21°C) (room tem-
perature). If the fluid level is correctly established at
room temperature, it should be between the“HOT”
(upper) reference holes when the transmission reaches
180°F (82°C). Remember it is best to check the level at the
normal operating temperature.CAUTION!
Be aware that if the fluid temperature is below 50°F
(10°C) it may not register on the dipstick. Do not add
fluid until the temperature is elevated enough to
produce an accurate reading.
7. Check for leaks. Release parking brake.
To prevent dirt and water from entering the transmission
after checking or replenishing fluid, make certain that the
dipstick cap is properly reseated. It is normal for the
dipstick cap to spring back slightly from its fully seated
position, as long as its seal remains engaged in the
dipstick tube.
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Special Additives
The manufacturer recommends against the addition of
any additives to the transmission. Exception to this
policy is the use of special dyes to aid in detecting fluid
leaks.
Transfer Case
Fluid Level Check
Inspect the transfer case for fluid leaks. If a fluid leak is
found, the transfer case fluid level can be checked by
removing the filler plug located on the back side of the
transfer case. The fluid level should be at the bottom edge
of the filler plug hole when the vehicle is in a level
position.
Adding Fluid
Add fluid at the filler hole until it runs out of the hole
when the vehicle is in a level position.
Drain
First remove fill plug, then remove drain plug. Recom-
mended tightening torque for drain and fill plugs is
15–25 ft. lbs (20–34 N·m).
CAUTION!
When installing plugs, do not overtighten. You could
damage them and cause them to leak.
Selection of Lubricant
Use only manufacturer’s recommended fluid, refer to
Fluids, Lubricants, and Genuine Parts for correct fluid
type.
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Front/Rear Axle Fluid
Front Axle Fluid Level Check
Lubricant should be to the bottom of the oil fill hole.
Rear Axle Fluid Level Check
Lubricant should be 1/2”(1 cm) below the oil fill hole.
Adding Fluid
Add lubricant only at the fill hole and only to the level
specified above.
Selection of Lubricant
Use only manufacturer’s recommended fluid, refer to
Fluids, Lubricants, and Genuine Parts for correct fluid
type.
Maintenance After Off-Pavement Driving
After extended operation in mud, sand or water, or
similar dirty conditions, have your brake discs, brake
linings, and axle joints inspected and cleaned as soon as
possible. This will prevent any abrasive material from
causing excessive wear or unpredictable braking action.
Following off-pavement usage, completely inspect the
underbody of your vehicle. Check tires, body structure,
steering, suspension and exhaust system for damage.
Check threaded fasteners for looseness, particularly on
the chassis, drivetrain components, steering and suspen-
sion. Retighten, if required, to torque values specified in
the Service Manual. Also check for accumulations of
vegetation or brush that could become a fire hazard, or
conceal damage to fuel lines, brake hoses, axle pinion
seals, and propeller shafts.
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7

CAUTION!
Under frequent heavy-duty driving conditions,
change all lubricants and lubricate body compo-
nents, all driveline joints and steering linkage more
often than in normal service to prevent excessive
wear.
Appearance Care And Protection From Corrosion
Protection of Body and Paint from Corrosion
Vehicle body care requirements vary according to geo-
graphic locations and usage. Chemicals that make roads
passable in snow and ice, and those that are sprayed on
trees and road surfaces during other seasons, are highly
corrosive to the metal in your vehicle.
The following maintenance recommendations will enable
you to obtain maximum benefit from the corrosion
resistance built into your vehicle.
What Causes Corrosion?
Corrosion is the result of deterioration or removal of
paint and protective coatings from your vehicle.
The most common causes are:
•Road salt, dirt and moisture accumulation.
•Stone and gravel impact.
•Insects, tree sap and tar.
•Salt in the air near seacoast localities.
•Atmospheric fallout/industrial pollutants.
Washing
•
Wash your vehicle regularly. Always wash your ve-
hicle in the shade using MoparCar Wash or a mild
car wash soap, and rinse the panels completely with
clear water.
376 MAINTAINING YOUR VEHICLE