2008 JEEP GRAND CHEROKEE fuel cap

CAUTION!
To avoid fuel spillage and overfilling, do not ªtop
offº the fuel tank after filling.
NOTE:When the fuel nozzle ªclicksº or shuts off, the
fuel tank is full.
WARNING!
²Never have any smoking materials lit in or near
the vehicle when the gas cap is removed or the
tank filled.
²Never add fuel when the engine is running. This is
in violation of most state and federal fire regula-
tions and will cause the malfunction indicator
light to turn on.NOTE:Tighten the gas cap about 1/4 turn until you
hear one click. This is an indication that cap is properly
tightened.
If the gas cap is not tighten properly, the Malfunction
Indicator Light will come on. Be sure the gas cap is
tightened every time the vehicle is refueled.
WARNING!
A fire may result if gasoline is pumped into a
portable container that is inside of a vehicle. You
could be burned. Always place gas containers on the
ground while filling.
STARTING AND OPERATING 347
5

Loose Fuel Filler Cap Message
If the vehicle diagnostic system determines that the fuel
filler cap is loose, improperly installed, or damaged, a
ªCHECK GASCAPº message will be displayed in the
EVIC (Electronic Vehicle Information Center). Refer to
ªElectronic Vehicle Information Centerº in Section 4 of
this manual. Tighten the fuel filler cap until a ªclickingº
sound is heard. This is an indication that the fuel filler
cap is properly tightened. Refer to ªOnboard Diagnostic
System Ð OBDIIº in Section 7 of this manual for more
information.
CAUTION!
Damage to the fuel system or emission control sys-
tem could result from using an improper fuel tank
filler cap (gas cap). A poorly fitting cap could let
impurities into the fuel system.
VEHICLE LOADING
Certification Label
As required by National Highway Traffic Safety Admin-
istration Regulations, your vehicle has a certification
label affixed to the driver's side door or pillar.
This label contains the month and year of manufacture,
Gross Vehicle Weight Rating (GVWR), Gross Axle Weight
Rating (GAWR) front and rear, and Vehicle Identification
Number (VIN). A Month-Day-Hour (MDH) number is
included on this label and indicates the Month, Day, and
Hour of manufacture. The bar code that appears on the
bottom of the label is your Vehicle Identification Number
(VIN).
Gross Vehicle Weight Rating (GVWR)
The GVWR is the total permissible weight of your vehicle
including driver, passengers, vehicle, options, trailer
348 STARTING AND OPERATING

tongue weight, and cargo. The label also specifies maxi-
mum capacities of front and rear axle systems (GAWR).
Total load must be limited, so GVWR, and front and rear
GAWR are not exceeded.
Payload
The payload of a vehicle is defined as the allowable load
weight a truck can carry, including the weight of the
driver, all passengers, options and cargo.
Gross Axle Weight Rating (GAWR)
The GAWR is the maximum permissible load on the front
and rear axles. The load must be distributed in the cargo
area so that the GAWR of each axle is not exceeded.
Each axle GAWR is determined by the components in the
system with the lowest load carrying capacity (axle,
springs, tires, or wheels). Heavier axles or suspension
components sometimes specified by purchasers for in-
creased durability does not necessarily increase the vehi-
cle's GVWR.
Tire Size
The tire size on the Label represents the actual tire size on
your vehicle. Replacement tires must be equal to the load
capacity of this tire size.
Rim Size
This is the rim size that is appropriate for the tire size
listed.
Inflation Pressure
This is the cold tire inflation pressure for your vehicle for
all loading conditions up to full GAWR.
Curb Weight
The curb weight of a vehicle is defined as the total weight
of the vehicle with all fluids, including vehicle fuel, at full
capacity conditions, and with no occupants or cargo
loaded into the vehicle. The front and rear curb weight
values are determined by weighing your vehicle on a
commercial scale before any occupants or cargo are
added.
STARTING AND OPERATING 349
5

MAINTAINING YOUR VEHICLE
CONTENTS
mEngine Compartment ± 3.7L...............386
mEngine Compartment ± 4.7L...............387
mEngine Compartment ± 5.7L...............388
mEngine Compartment ± 3.0L Diesel..........389
mOnboard Diagnostic System Ð OBD II........390
NLoose Fuel Filler Cap Message............391
mEmissions Inspection And Maintenance
Programs............................391
mReplacement Parts......................393mDealer Service.........................393
mMaintenance Procedures..................394
NEngine Oil..........................394
NDrive Belts Ð Check Condition And Tension . . 398
NSpark Plugs.........................398
NSpark Plug Wires.....................398
NEngine Air Cleaner Filter................398
NCatalytic Converter....................399
NCrankcase Emission Control System........400
7

Loose Fuel Filler Cap Message
After fuel is added, the vehicle diagnostic system can
determine if the fuel filler cap is loose, improperly
installed, or damaged. A ªCHECK GASCAPº message
will be displayed in the EVIC (Refer to Section 4 of this
manual). Tighten the gas cap until a9clicking9sound is
heard. This is an indication that the gas cap is properly
tightened.
This message may be temporarily overridden by pressing
either the C/T, STEP, or MENU buttons. However, after
one minute of no customer interaction, the EVIC will
display again the ªCHECK GASCAPº message. The
message will remain displayed until the vehicle diagnos-
tic system can retest the fuel system. The test will
perform the next time the vehicle is started, if the vehicle
was keyed off above 40ÉF (4ÉC) outside temperature and
the following vehicle start is above 40ÉF (4ÉC) outside
temperature. It may be possible to have a message that
will not clear due to the test being disabled due to lowoutside temperatures. If the test is performed and the
problem is gone, the message will disappear.
If the problem persists, the message will appear the next
time the vehicle is started. This might indicate a damaged
cap. If the problem is detected twice in a row, the system
will turn on the Malfunction Indicator Light (MIL).
Resolving the problem will turn the MIL light off. See
your authorized dealer for service.
EMISSIONS INSPECTION AND MAINTENANCE
PROGRAMS
In some localities, it may be a legal requirement to pass
an inspection of your vehicle's emissions control system.
Failure to pass could prevent vehicle registration.
For states which have an I/M (Inspection and
Maintenance) requirement, this check verifies the
following: the MIL (Malfunction Indicator Lamp)
MAINTAINING YOUR VEHICLE 391
7

Engine Oil Viscosity (3.7L/4.7L/5.7L Engines)
SAE 5W-20 engine oil is recommended for all operating
temperatures. This engine oil improves low temperature
starting and vehicle fuel economy.
The engine oil filler cap also shows the recommended
engine oil viscosity for your vehicle. For information on
engine oil filler cap location, see the ªEngine Compart-
mentº illustration in this section.
NOTE:Vehicles equipped with a 5.7L engine must use
SAE 5W-20 oil. Failure to do so may result in improper
operation of the Multiple Displacement System (MDS).
Refer to ªMulti Displacement Systemº in Section 5 for
more details.
Lubricants which do not have both, the engine oil certi-
fication mark and the correct SAE viscosity grade num-
ber should not be used.
Engine Oil Viscosity (3.0L Diesel Engine)
CAUTION!
Your vehicle is equipped with an advanced technol-
ogy Diesel Engine and an emission device designed
to limit Diesel Particulate Emissions from being
released into the atmosphere. The durability of your
engine and life expectancy of this diesel particulate
filter emission device is highly dependent on the use
of the correct engine oil.
In order to protect your engine and emission system, use
only SAE 5W-30 Synthetic Engine Oil that meets
DaimlerChrysler Material Standard MS-11106, Mercedes
Benz MB 229.31 or MB 229.51, and ACEA C3 qualified
engine oils.
396 MAINTAINING YOUR VEHICLE

You are urged to use only the manufactures-specified
tubes, connections and clamps, or their equivalent in
material and specification, in any fuel system servicing.
Brake System
In order to assure brake system performance, all brake
system components should be inspected periodically.
Refer to the 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.
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.
MAINTAINING YOUR VEHICLE 413
7

CAUTION!
Be aware that if the fluid temperature is below 50ÉF
(10ÉC) 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.
Maintenance After Off-Road 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.
After driving off-road, 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 suspension.
Retighten, if required, to torque values specified in the
Service Manual. Also check for accumulations of vegeta-
tion or brush that could become a fire hazard, or conceal
damage to fuel lines, brake hoses, axle pinion seals, and
propeller shafts.
420 MAINTAINING YOUR VEHICLE