2007 JEEP GRAND CHEROKEE engine

for any accumulation of bugs, leaves, etc. If dirty, clean by
gently spraying water from a garden hose vertically
down the face of the condenser.
Check the engine cooling system hoses for brittle rubber,
cracking, tears, cuts, and tightness of the connection at
the coolant recovery bottle and radiator. Inspect the
entire system for leaks.
With the engine at normal operating temperature (but
not running), check the cooling system pressure cap for
proper vacuum sealing by draining a small amount of
coolant from the radiator drain cock. If the cap is sealing
properly, the antifreeze/coolant will begin to drain from
the coolant recovery bottle. DO NOT REMOVE THE
COOLANT PRESSURE CAP WHEN THE COOLING
SYSTEM IS HOT.Cooling System — Drain, Flush, And Refill
At the intervals shown in the appropriate “Maintenance
Schedule,” the system should be drained, flushed, and
refilled.
If the solution is dirty and contains a considerable
amount of sediment, clean and flush with reliable cooling
system cleaner. Follow with a thorough rinsing to remove
all deposits and chemicals. Properly dispose of old
antifreeze/coolant solution.
Selection Of Coolant
Use only the manufacturer’s recommended antifreeze/
coolant, refer to Fluids, Lubricants, and Genuine Parts for
correct antifreeze/coolant type.
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CAUTION!
Mixing of antifreeze/coolant other than the specified
HOAT antifreeze/coolant may result in decreased
corrosion protection and engine damage. If a non-
HOAT antifreeze/coolant is introduced into the cool-
ing system in an emergency, it should be replaced
with the specified antifreeze/coolant as soon as pos-
sible.
Do not use plain water alone or alcohol base
antifreeze/coolant products. Do not use additional
rust inhibitors or antirust products, as they may not
be compatible with the antifreeze/coolant and may
plug the radiator.
This vehicle has not been designed for use with
Propylene Glycol based antifreeze/coolant. Use of
Propylene Glycol base antifreeze/coolant is not rec-
ommended.
Adding Coolant
Your vehicle has been built with an improved antifreeze/
coolant that allows extended maintenance intervals. This
antifreeze/coolant can be used up to 5 Years or 100,000
miles before replacement. To prevent reducing this ex-
tended maintenance period, it is important that you use
the same antifreeze/coolant throughout the life of your
vehicle. Please review these recommendations for using
Hybrid Organic Additive Technology (HOAT)
antifreeze/coolant.
When adding antifreeze/coolant, a minimum solution of
50% recommended MoparAntifreeze/ Coolant 5 Year/
100,000 Mile Formula HOAT (Hybrid Organic Additive
Technology), or equivalent, in water should be used. Use
higher concentrations (not to exceed 70%) if temperatures
below -34°F (-37°C) are anticipated.
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Use only high purity water such as distilled or deionized
water when mixing the water/antifreeze (coolant) solu-
tion. The use of lower quality water will reduce the
amount of corrosion protection in the engine cooling
system.
Please note that it is the owner’s responsibility to main-
tain the proper level of protection against freezing ac-
cording to the temperatures occurring in the area where
the vehicle is operated.
NOTE:Mixing antifreeze/coolant types will decrease
the life of the antifreeze/coolant and will require more
frequent antifreeze/coolant changes.
Cooling System Pressure Cap
The cap must be fully tightened to prevent loss of
antifreeze/coolant, and to insure that antifreeze/coolant
will return to the radiator from the coolant recovery tank.The cap should be inspected and cleaned if there is any
accumulation of foreign material on the sealing surfaces.
WARNING!
•The warning words DO NOT OPEN HOT on the
cooling system pressure cap are a safety precau-
tion. Never add antifreeze/coolant when the en-
gine is overheated. Do not loosen or remove the
cap to cool an overheated engine. Heat causes
pressure to build up in the cooling system. To
prevent scalding or injury, do not remove the
pressure cap while the system is hot or under
pressure.
•Do not use a pressure cap other than the one
specified for your vehicle. Personal injury or
engine damage may result.
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Disposal of Used Engine Coolant
Used ethylene glycol-based antifreeze/coolant is a regu-
lated substance requiring proper disposal. Check with
your local authorities to determine the disposal rules for
your community. To prevent ingestion by animals and
children, do not store ethylene glycol-based antifreeze/
coolant in open containers or allow it to remain in
puddles on the ground. If ingested by a child, contact a
physician immediately. Clean up any ground spills im-
mediately.
Coolant Level
The coolant bottle provides a quick visual method for
determining that the antifreeze/coolant level is adequate.
With the engine idling, and warm to normal operating
temperature, the level of the antifreeze/coolant in the
bottle should be between the ranges indicated on the
bottle.The radiator normally remains completely full, so there is
not need to remove the radiator cap unless checking for
antifreeze/coolant freeze point or replacing antifreeze/
coolant. Advise your service attendant of this. As long as
the engine operating temperature is satisfactory, the
coolant bottle need only be checked once a month.
When additional antifreeze/coolant is needed to main-
tain the proper level, it should be added to the coolant
bottle. Do not overfill.
Points To Remember
NOTE:When the vehicle is stopped after a few miles
(kilometers) of operation, you may observe vapor coming
from the front of the engine compartment. This is nor-
mally a result of moisture from rain, snow, or high
humidity accumulating on the radiator and being vapor-
ized when the thermostat opens, allowing hot antifreeze/
coolant to enter the radiator.
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If an examination of your engine compartment shows no
evidence of radiator or hose leaks, the vehicle may be
safely driven. The vapor will soon dissipate.
•Do not overfill the coolant recovery bottle.
•Check antifreeze/coolant freeze point in the radiator
and in the coolant recovery bottle. If antifreeze/
coolant needs to be added, contents of coolant recov-
ery bottle must also be protected against freezing.
•If frequent antifreeze/coolant additions are required,
or if the level in the coolant recovery bottle does not
drop when the engine cools, the cooling system should
be pressure tested for leaks.
•Maintain antifreeze/coolant concentration at 50%
HOAT antifreeze/coolant (minimum) and distilled
water for proper corrosion protection of your engine
which contains aluminum components.
•Make sure that the radiator and coolant recovery
bottle hoses are not kinked or obstructed.
•Keep the front of the radiator clean. If your vehicle is
equipped with air conditioning, keep the front of the
condenser clean, also.
•Do not change the thermostat for summer or winter
operation. If replacement is ever necessary, install
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.
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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 performed
whenever the brake system is serviced and every engine
oil change. Inspect hydraulic brake hoses for surface
cracking, scuffing, or worn spots. If there is any evidence
of cracking, scuffing, or worn spots, the hose should be
replaced immediately! Eventual deterioration of the hose
can take place resulting in a possibility of a burst failure.
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.
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Brake Master Cylinder — Brake Fluid Level Check
The fluid level of the master cylinder should be checked
when performing under the hood service, or immedi-
ately if the brake system warning lamp indicates system
failure.
The brake master cylinder has a translucent plastic
reservoir. On the outboard side of the reservoir, there is a
“MAX” dot and an “MIN” dot. The fluid level must be
kept within these two dots. Do not add fluid above the
MAX mark, because leakage may occur at the cap.
With disc brakes the fluid level can be expected to fall as
the brake linings wear. However, an unexpected drop in
fluid level may be caused by a leak and a system check
should be conducted.
Refer to Fluids, Lubricants and Genuine Parts for the
correct fluid type.WARNING!
Use of a brake fluid that may have a lower initial
boiling point, or is unidentified as to specification,
may result in sudden brake failure during hard
prolonged 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 or
moisture.
384 MAINTAINING YOUR VEHICLE

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.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.
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