2006 JEEP GRAND CHEROKEE SRT Owners Manual

Exhaust System
The best protection against carbon monoxide entry into
the vehicle body is a properly maintained engine exhaust
system.
Whenever a change is noticed in the sound of the exhaust
system, when exhaust fumes can be detected inside the
vehicle, or when the underside or rear of the vehicle is
damaged, have a competent mechanic inspect the com-
plete exhaust system and adjacent body areas for broken,
damaged, deteriorated, or mispositioned parts. Open
seams or loose connections could permit exhaust fumes
to seep into the passenger compartment. In addition,
inspect the exhaust system each time the vehicle is raised
for lubrication or oil change. Replace as required.WARNING!
Exhaust gases can injure or kill. They contain carbon
monoxide (CO) which is colorless and odorless.
Breathing it can make you unconscious and can
eventually poison you. To avoid breathing CO, fol-
low the preceding safety tips.
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7

Cooling System
WARNING!
•When working near the radiator cooling fan, dis-
connect the fan motor lead or turn the ignition
switch to the OFF position. The fan is temperature
controlled and can start at any time the ignition
switch is in the ON position.
•You or others can be badly burned by hot coolant
or steam from your radiator. If you see or hear
steam coming from under the hood, don’t open
the hood until the radiator has had time to cool.
Never try to open a cooling system pressure cap
when the radiator is hot.
Coolant Checks
Check engine coolant (antifreeze) protection every 12
months (before the onset of freezing weather, whereapplicable). If coolant is dirty or rusty in appearance, the
system should be drained, flushed and refilled with fresh
coolant. Check the front of the A/C condenser 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 coolant recovery bottle tubing for brittle rub-
ber, cracking, tears, cuts and tightness of the connection
at the 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 engine coolant (antifreeze) will begin to
drain from the coolant recovery bottle. DO NOT RE-
MOVE THE COOLANT PRESSURE CAP WHEN THE
COOLING SYSTEM IS HOT.
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Cooling System — Drain, Flush and Refill
At the intervals shown on the appropriate “Maintenance
Schedule,” the system should be drained, flushed and
refilled.
If the solution is dirty or contains a considerable amount
of sediment, clean and flush with a reliable cooling
system cleaner. Follow with a thorough rinsing to remove
all deposits and chemicals. Properly dispose of old
antifreeze solution.
Selection Of Coolant
Use only the manufacturer’s recommended coolant, refer
to Fluids, Lubricants and Genuine Parts for correct
coolant type.
CAUTION!
Mixing of coolants other than specified HOAT en-
gine coolants, may result in engine damage and may
decrease corrosion protection. If a non-HOAT cool-
ant is introduced into the cooling system in an
emergency, it should be replaced with the specified
coolant as soon as possible.
Do not use plain water alone or alcohol base engine
coolant (antifreeze) products. Do not use additional
rust inhibitors or antirust products, as they may not
be compatible with the radiator engine coolant and
may plug the radiator.
This vehicle has not been designed for use with
Propylene Glycol based coolants. Use of Propylene
Glycol based coolants is not recommended.
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7

Adding Coolant
Your vehicle has been built with an improved engine
coolant that allows extended maintenance intervals. This
coolant can be used up to 5 Years or 100,000 miles before
replacement. To prevent reducing this extended mainte-
nance period, it is important that you use the same
coolant throughout the life of your vehicle. Please review
these recommendations for using Hybrid Organic Addi-
tive Technology (HOAT) coolant.
When adding coolant, a minimum solution of 50% rec-
ommended Mopar Antifreeze/ Coolant 5 Year/100,000
Mile Formula HOAT (Hybrid Organic Additive Technol-
ogy), or equivalent, in water should be used. Use higher
concentrations (not to exceed 70%) if temperatures below

34°F (
37°C ) are anticipated.
Use only high purity water such as distilled or deionized
water when mixing the water/engine coolant solution.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 coolant types will decrease the life of the
engine coolant and will require more frequent coolant
changes.
Cooling System Pressure Cap
The cap must be fully tightened to prevent loss of
coolant, and to insure that coolant will return to the
radiator from the coolant recovery bottle.
The cap should be inspected and cleaned if there is any
accumulation of foreign material on the sealing surfaces.
316 MAINTAINING YOUR VEHICLE

WARNING!
•The warning words “DO NOT OPEN HOT” on
the cooling system pressure cap are a safety pre-
caution. Never add coolant when the engine 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.
Disposal of Used Engine Coolant
Used ethylene glycol based engine coolant is a regulated
substance requiring proper disposal. Check with your
local authorities to determine the disposal rules for your
community. To prevent ingestion by animals or childrendo not store ethylene glycol based engine 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 immediately.
Coolant Level
The coolant bottle provides a quick visual method for
determining that the coolant level is adequate. With the
engine off and cold, the level of the coolant in the bottle
should be between the ranges indicated on the bottle.
The radiator normally remains completely full, so there is
no need to remove the radiator cap unless checking for
coolant freeze point or replacing 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 coolant is needed to maintain the
proper level, it should be added to the coolant bottle. Do
not overfill.
MAINTAINING YOUR VEHICLE 317
7

Points To Remember
NOTE:When the vehicle is stopped after a few miles (a
few kilometers) of operation, you may observe vapor
coming from the front of the engine compartment. This is
normally a result of moisture from rain, snow, or high
humidity accumulating on the radiator and being vapor-
ized when the thermostat opens, allowing hot coolant to
enter the radiator.
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 coolant freeze point in the radiator and in the
coolant recovery bottle. If antifreeze needs to be
added, contents of coolant recovery bottle must also be
protected against freezing.
•If frequent 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 pres-
sure tested for leaks.
•Maintain coolant concentration at 50% HOAT engine
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 overflow 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
318 MAINTAINING YOUR VEHICLE

ONLY the correct type thermostat. Other designs may
result in unsatisfactory coolant 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 those hoses nearest to high
heat sources such as the exhaust manifold. Inspect hose
routing to be sure hoses do not come in contact with any
heat source or moving component which 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 cou-
plings to make sure they are secure and no leaks are
present.
Components should be replaced immediately if there is
any evidence of wear or damage that could cause failure.
Brake System
In order to assure brake system performance, all brake
system components should be inspected periodically.
Suggested service intervals can be found on the appro-
priate “Maintenance Schedule.” Refer to Section 8 of this
manual.
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7

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.
Brake And Power Steering Hoses
When the vehicle is serviced for scheduled maintenance,
inspect surface of hoses and nylon tubing for evidence of
heat and mechanical damage. Hard and brittle rubber,
cracking, tears, cuts, abrasion, and excessive swelling
indicate deterioration of the rubber. Particular attention
should be made to examining those hose surfaces nearest
to high heat sources, such as the exhaust manifold.Insure nylon tubing in these areas has not melted or
collapsed.
Inspect all hose connections such as clamps and cou-
plings to make sure they are secure and no leaks are
present.
NOTE:Often, fluid such as oil, power steering fluid,
and brake fluid are used during assembly plant opera-
tions to facilitate the assembly of hoses to couplings.
Therefore, oil wetness at the hose-coupling area is not
necessarily an indication of leakage. Actual dripping of
hot fluid when systems are under pressure (during
vehicle operation), should be noted before a hose is
replaced based on leakage.
NOTE:Inspection of brake hoses should be performed
whenever the brake system is serviced and at 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
320 MAINTAINING YOUR VEHICLE