JEEP WRANGLER UNLIMITED 2008 Owners Manual

ADDING FUEL
Fuel Filler Cap (Gas Cap)
The gas cap is located on the driver’s side of the vehicle.
If the gas cap is lost or damaged, be sure the replacement
cap is the correct one for this vehicle.
Loose Fuel Filler Cap Message (gASCAP)
After fuel has been added, the vehicle diagnostic system
can determine if the fuel filler cap is possibly loose,
improperly installed, or damaged. If the system detects a
malfunction, the “gASCAP” message will display in the
odometer display. Tighten the gas cap until aclicking
sound is heard. This is an indication that the gas cap is
properly tightened. Press the odometer reset button to
turn the message off. 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. Resolving the problem will turn the MIL
light off.

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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.
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 B-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 isincluded 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 VIN.
Gross Vehicle Weight Rating (GVWR)
The GVWR is the total permissible weight of your vehicle
including driver, passengers, vehicle, options, trailer
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.
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the front or rear axles has been exceeded, but the total
load is within the specified GVWR. If so, weight must be
shifted from front to rear, or rear to front, as appropriate
until the specified weight limitations are met. Store the
heavier items down low and be sure that the weight is
distributed equally. Stow all loose items securely before
driving.
Improper weight distributions can have an adverse affect
on the way your vehicle steers and handles, and the way
the brakes operate.

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Trailer Tongue Weight (TW)
The trailer tongue weight is the downward force exerted
on the hitch ball by the trailer. In most cases it should not
be less than 10% or more than 15% of the trailer load. You
must consider this as part of the load on your vehicle.
Frontal Area
The frontal area is the maximum height and maximum
width of the front of a trailer.
Trailer Sway Control
The trailer sway control is a telescoping link that can be
installed between the hitch receiver and the trailer
tongue. It typically provides adjustable friction associ-
ated with the telescoping motion to dampen any un-
wanted trailer swaying motions while traveling.
Weight-Carrying Hitch
A weight-carrying hitch supports the trailer tongue
weight, just as if it were luggage located at a hitch ball or
some other connecting point of the vehicle. This kind ofhitch is the most popular on the market today and is
commonly used to tow small and medium-sized trailers.
Weight-Distributing Hitch
A weight-distributing hitch system works by applying
leverage through spring (load) bars. It is typically used
for heavier loads, to distribute trailer tongue weight to
the tow vehicle’s front axle and the trailer axle(s). When
used in accordance with the manufacturers’ directions, it
provides for a more level ride, offering more consistent
steering and brake control thereby enhancing towing
safety. The addition of a friction/hydraulic sway control
also dampens sway caused by traffic and crosswinds,
and contributes positively to tow vehicle and trailer
stability. Trailer sway control and a weight-distributing
(load-equalizing) hitch are recommended for heavier
tongue weights (TW) and may be required depending on
vehicle and trailer configuration/loading to comply with
Gross Axle Weight Rating (GAWR) requirements.
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Trailer Hitch Classification
The following chart provides the industry standard for
the maximum trailer weight a given trailer hitch class can
tow and should be used to assist you in selecting the
correct trailer hitch for your intended towing condition.Refer to the Trailer Towing Weights (Maximum Trailer
Weight Ratings) chart for the Max. GTW towable for your
given drivetrain.

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