2008 JEEP GRAND CHEROKEE SRT Owners Manual

NOTE:Fill engine oil one quart at a time.
CAUTION!
Overfilling or underfilling will cause oil aeration or
loss of oil pressure. This could damage your engine.
CAUTION!
Operating the engine with the oil levels below the
safe zone, or operating with oil levels that exceed the
top of the safe zone may cause engine damage.
Change Engine Oil
Road conditions and your kind of driving affects the
interval at which your oil should be changed. Check the
following list to see if any apply to you.
²Day or night temperatures are below 32ÉF (0ÉC).
²Stop and go driving.
²Extensive engine idling.
²Driving in dusty conditions.
²Short trips of less than 10 miles (16 km).
Engine Oil Dipstick
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²More than 50% of your driving is at sustained high
speeds during hot weather, above 90ÉF (32ÉC).
²Trailer towing.
NOTE:IfANYof these apply to you then change your
engine oil every 3,000 miles (5 000 km) or 3 months,
whichever comes first. Refer to ªMaintenance Schedule
Bº in Section 8 of this manual.
If none of these apply to you, then change your engine oil
at every interval shown on ªMaintenance Schedule9A.9
Refer to Section 8 of this manual.NOTE:Under no circumstances should oil change in-
tervals exceed 6,000 miles (10 000 km) or 6 months
whichever comes first.
Engine Oil Selection
For best performance and maximum protection under all
types of operating conditions, the manufacturer only
recommends full synthetic engine oils that meet the
American Petroleum Institute (API) categories of SM or
SM/CF, and meet the requirements of DaimlerChrysler
Material Standard MS-10725.
The manufacturer recommends the use of a full synthetic
engine oil, such as Mobil 1tSAE 0W-40 or equivalent.
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Engine Oil Viscosity
SAE 0W-40 engine oil is preferred for use within the
operating temperatures shown in the engine oil viscosity
chart. SAE 5W-40 engine oil is also allowed. The proper
SAE viscosity grade of engine oil should be selected
based on the following recommendation and be within
the operating temperature shown in the engine oil vis-
cosity chart.
The engine oil filler cap also shows the recommended
engine oil viscosity for your engine. For information on
engine oil filler cap location, refer to the ªEngine Com-
partmentº illustration in this section.
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Synthetic Engine Oils
You may use synthetic engine oils provided the recom-
mended oil quality requirements are met, and the recom-
mended maintenance intervals for oil and filter changes
are followed.
Materials Added to Engine Oil
The manufacturer strongly recommends against the ad-
dition of any additives (other than leak detection dyes) to
the engine oil. Engine oil is an engineered product and
it's performance may be impaired by supplemental ad-
ditives.
Disposing of Used Engine Oil And Oil Filters
Care should be taken in disposing of used engine oil and
oil filters from your vehicle. Used oil and oil filters,
indiscriminately discarded, can present a problem to the
environment. Contact your dealer, service station, or
governmental agency for advice on how and where used
oil and oil filters can be safely discarded in your area.
Engine Oil Filter
The engine oil filter should be replaced at every engine
oil change.
Engine Oil Filter Selection
The manufacturer's engines have a full-flow type oil
filter. Use a filter of this type for replacement. The quality
of replacement filters varies considerably. Only high
quality filters should be used to assure most efficient
service. Mopar Engine Oil Filters are a high quality oil
filter and are recommended.
Drive Belts Ð 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.
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At the mileage indicated on the appropriate ªMainte-
nance Schedule,º all belts and tensioner should be
checked for condition. Improper belt tension can cause
belt slippage and failure.
Belts should be inspected for evidence of cuts, cracks,
glazing, or frayed cords and replaced if there is indication
of damage which could result in belt failure. Low gen-
erator belt tension can cause battery failure.
Also check belt routing to make sure there is no interfer-
ence between the belts and other engine components.
Spark Plugs
Spark plugs must fire properly to assure engine perfor-
mance and emission control. New spark plugs should be
installed at the specified mileage. The entire set should be
replaced if there is any malfunction due to a faulty spark
plug. Refer to ªFluids, Lubricants, and Genuine Partsº in
this section for spark plug information.
Engine Air Cleaner Filter
Under normal driving conditions, replace the air filter at
the intervals shown on ªMaintenance Schedule A.º If,
however, you drive the vehicle frequently under dusty or
severe conditions, the filter element should be inspected
periodically and replaced if necessary at the intervals
shown on ªMaintenance Schedule B.º
WARNING!
The air cleaner can provide a measure of protection
in the case of engine backfire. Do not remove the air
cleaner unless such removal is necessary for repair or
maintenance. Make sure that no one is near the
engine compartment before starting the vehicle with
the air cleaner removed. Failure to do so can result in
serious personal injury.
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Fuel Filter
A plugged fuel filter can cause stalling, limit the speed at
which a vehicle can be driven or cause hard starting.
Should an excessive amount of dirt accumulate in the
fuel tank, filter replacement may be necessary. See your
local dealer for service.
Catalytic Converter
The catalytic converter requires the use of unleaded fuel
only. Leaded gasoline will destroy the effectiveness of the
catalyst as an emission control device.
Under normal operating conditions, the catalytic con-
verter will not require maintenance. However, it is im-
portant to keep the engine properly tuned to assure
proper catalyst operation and prevent possible catalyst
damage.
CAUTION!
Damage to the catalytic converter can result if your
vehicle is not kept in proper operating condition. In
the event of engine malfunction, particularly involv-
ing engine misfire or other apparent loss of perfor-
mance, have your vehicle serviced promptly. Contin-
ued operation of your vehicle with a severe
malfunction could cause the converter to overheat,
resulting in possible damage to the converter and the
vehicle.
NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
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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 exhaust
system. Do not park or operate your vehicle in areas
where your exhaust system can contact anything that
can burn.
In unusual situations involving grossly malfunctioning
engine operation, a scorching odor may indicate severe
and abnormal catalyst overheating. If this occurs, the
vehicle should be stopped, the engine shut off and the
vehicle allowed to cool. Thereafter, service, including a
tune-up to manufacturer's specifications, should be ob-
tained immediately.To minimize the possibility of catalyst damage:²Do not shut off the engine or interrupt the ignition
when the transmission is in gear and the vehicle is in
motion.
²Do not try to start engine by pushing or towing the
vehicle.
²Do not idle the engine with any spark plug wires
disconnected or removed, such as when diagnostic
testing, or for prolonged periods during very rough
idling or malfunctioning operating conditions.
Maintenance-Free Battery
Your vehicle is equipped with a maintenance-free battery.
You will never have to add water, nor is periodic main-
tenance required.
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CAUTION!
It is essential when replacing the cables on the
battery that the positive cable is attached to the
positive post and the negative cable is attached to the
negative post. Battery posts are marked (+) positive
and negative (-) and identified on the battery case.
Also, if a ªfast chargerº is used while battery is in the
vehicle, disconnect both vehicle battery cables before
connecting the charger to battery. Do not use a ªfast
chargerº to provide starting voltage.
Air Conditioner Maintenance
For best possible performance, your air conditioner
should be checked and serviced by an Authorized Dealer
at the start of each warm season. This service shouldinclude cleaning of the condenser fins and a performance
test. Drive belt tension should also be checked at this
time.
WARNING!
²Use only refrigerants and compressor lubricants
approved by the manufacturer for your air condi-
tioning system. Some unapproved refrigerants are
flammable and can explode, injuring you. Other
unapproved refrigerants or lubricants can cause
the system to fail, requiring costly repairs. Refer
to Section 3 of the Warranty Information Book for
further warranty information.
²The air conditioning system contains refrigerant
under high pressure. To avoid risk of personal
injury or damage to the system, adding refrigerant
or any repair requiring lines to be disconnected
should be done by an experienced repairman.
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