Jeep TJ (2006 year). Manual — part 15

WARNING!

Fast spinning tires can be dangerous. Forces gener-
ated by excessive wheel speeds may cause tire dam-
age or failure. A tire could explode and injure
someone. Do not spin your vehicle’s wheels faster
than 35 mph (55 km/h) when you are stuck, and do
not let anyone near a spinning wheel no matter what
the speed.

Tread Wear Indicators
Tread wear indicators are in the original equipment tires
to help you in determining when your tires should be
replaced.

These indicators are molded into the bottom of the tread
grooves and will appear as bands when the tread depth
becomes 1/16 inch (2 mm). When the indicators appear
in 2 or more adjacent grooves, the tire should be replaced.

Many states have laws requiring tire replacement at this
point.

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Life of Tire
The service life of a tire is dependent upon varying
factors including but not limited to:

• Driving style
• Tire pressure
• Distance driven

WARNING!

Tires and spare tire should be replaced after six
years, regardless of the remaining tread. Failure to
follow this warning can result in sudden tire failure.
You could lose control and have an accident result-
ing in serious injury or death.

Keep unmounted tires in a cool, dry place with as little
exposure to light as possible. Protect tires from contact
with oil, grease and gasoline.

Replacement Tires
The tires on your new vehicle provide a balance of many
characteristics. They should be inspected regularly for
wear and correct cold tire inflation pressure. The manu-
facturer strongly recommends that you use tires equiva-
lent to the originals in size, quality and performance
when replacement is needed (see the paragraph on tread
wear indicators). Refer to the Tire and Loading Informa-
tion placard for the size designation of your tire. The
service description and load identification will be found
on the original equipment tire. Failure to use equivalent
replacement tires may adversely affect the safety, han-
dling, and ride of your vehicle. We recommend that you
contact your original equipment or an authorized tire
dealer with any questions you may have on tire specifi-
cations or capability.

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WARNING!

•

Do not use a tire, wheel size or rating other than that
specified for your vehicle. Some combinations of un-
approved tires and wheels may change suspension
dimensions and performance characteristics, resulting
in changes to steering, handling, and braking of your
vehicle. This can cause unpredictable handling and
stress to steering and suspension components. You
could lose control and have an accident resulting in
serious injury or death. Use only the tire and wheel
sizes with load ratings approved for your vehicle.

•

Never use a tire with a smaller load index or capacity,
other than what was originally equipped on your
vehicle. Using a tire with a smaller load index could
result in tire overloading and failure. You could lose
control and have an accident.

•

Failure to equip your vehicle with tires having ad-
equate speed capability can result in sudden tire
failure and loss of vehicle control.

CAUTION!

Replacing original tires with tires of a different size
may result in false speedometer and odometer read-
ings.

Alignment and Balance
Poor suspension alignment may result in:

• Fast tire wear.
• Uneven tire wear, such as feathering and one-sided

wear.

• Vehicle pull to right or left.

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Tires may also cause the vehicle to pull left or right.
Alignment will not correct this problem. See your autho-
rized dealer for proper diagnosis.

Improper alignment will not cause vehicle vibration.
Vibration may be a result of tire and wheel out-of-
balance. Proper balancing will reduce vibration and
avoid tire cupping and spotty wear.

TIRE CHAINS
Install chains on rear tires only. Tire chains may be
installed on all models except the Sahara and Rubicon.
Follow these recommendations to guard against damage
and excessive tire and chain wear:

• Use chains on P215/75R15 tires only. P225/75R15,

LT30 x 9.50R15, and LT245/75R16 tires do not provide
adequate clearance.

• Use SAE class “S” tire chains or traction devices only.

• Chains must be the proper size for the vehicle, as

recommended by the chain manufacturer.

• Follow tire chain manufacturer’s instructions for

mounting chains.

• Install chains snugly and tighten after.6 mile (1 km) of

driving.

• Do not exceed 30 mph (48 km/h).
• Drive cautiously, avoiding large bumps, potholes and

extreme driving maneuvers.

TIRE ROTATION RECOMMENDATIONS
Tires on the front and rear axles of vehicles operate at
different loads and perform different steering, handling,
and braking functions. For these reasons, they wear at
unequal rates, and develop irregular wear patterns.

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These effects can be reduced by timely rotation of tires.
The benefits of rotation are especially worthwhile with
aggressive tread designs such as those on On/Off Road
type tires. Rotation will increase tread life, help to main-
tain mud, snow, and wet traction levels, and contribute to
a smooth, quiet ride.

Follow the recommended tire rotation frequency for your
type of driving found in the “Maintenance Schedules”
Section of this manual. More frequent rotation is permis-
sible if desired. The reasons for any rapid or unusual
wear should be corrected prior to rotation being per-
formed.

The suggested rotation method is the “forward-cross”
shown in the following diagram.

FUEL REQUIREMENTS

Your engine is designed to meet all emis-
sions regulations and provide excellent
fuel economy and performance when us-
ing high quality unleaded gasoline having
an octane rating of 87. The use of premium
gasoline is not recommended. The use of

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premium gasoline will provide no benefit over high
quality regular gasoline, and in some circumstances may
result in poorer performance.

Light spark knock at low engine speeds is not harmful to
your engine. However, continued heavy spark knock at
high speeds can cause damage and immediate service is
required.

Poor quality gasoline can cause problems such as hard
starting, stalling and hesitations. If you experience these
symptoms, try another brand of gasoline before consid-
ering service for the vehicle.

Over 40 auto manufacturer’s world wide have issued and
endorsed consistent gasoline specifications (the World-
wide Fuel Charter, WWFC) to define fuel properties
necessary to deliver enhanced emissions, performance,
and durability for your vehicle. The manufacturer recom-
mends the use of gasoline that meets the WWFC speci-
fications if they are available.

Reformulated Gasoline
Many areas of the country require the use of cleaner
burning gasoline referred to as Reformulated Gasoline.
Reformulated gasoline contains oxygenates, and is spe-
cifically blended to reduce vehicle emissions and im-
prove air quality.

The manufacturer strongly supports the use of reformu-
lated gasoline. Properly blended reformulated gasoline
will provide excellent performance and durability for the
engine and fuel system components.

Gasoline/Oxygenate Blends
Some fuel suppliers blend unleaded gasoline with oxy-
genates such as 10% ethanol, MTBE, and ETBE. Oxygen-
ates are required in some areas of the country during the
winter months to reduce carbon monoxide emissions.
Fuels blended with these oxygenates may be used in
your vehicle.

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CAUTION!

DO NOT use gasoline containing METHANOL.
Gasoline containing methanol may damage critical
fuel system components.

MMT In Gasoline
MMT is a manganese containing metallic additive that is
blended into some gasoline to increase octane. Gasoline
blended with MMT provides no performance advantage
beyond gasoline of the same octane number without
MMT. Gasoline blended with MMT reduces spark plug
life and reduces emission system performance in some
vehicles. The manufacturer recommends that gasoline
without MMT be used in your vehicle. The MMT content
of gasoline may not be indicated on the gasoline pump,
therefore, you should ask your gasoline retailer whether
or not his/her gasoline contains MMT.

It is even more important to look for gasoline without
MMT in Canada because MMT can be used at levels
higher than allowed in the United States. MMT is pro-
hibited in Federal and California reformulated gasoline.

Materials Added To Fuel
All gasoline sold in the United States is required to
contain effective detergent additives. Use of additional
detergents or other additives is not needed under normal
conditions.

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Fuel System Cautions

CAUTION!

Follow these guidelines to maintain your vehicle’s
performance:

• The use of leaded gas is prohibited by Federal law.

Using leaded gasoline can impair engine performance,
damage the emission control system.

• An out-of-tune engine, or certain fuel or ignition

malfunctions, can cause the catalytic converter to
overheat. If you notice a pungent burning odor or
some light smoke, your engine may be out of tune or
malfunctioning and may require immediate service.
Contact your dealer for service assistance.

• The use of fuel additives which are now being sold as

octane enhancers is not recommended. Most of these
products contain high concentrations of methanol.

Fuel system damage or vehicle performance problems
resulting from the use of such fuels or additives is not
the responsibility of the manufacturer.

NOTE:

Intentional tampering with emissions control

systems can result in civil penalties being assessed
against you.

Carbon Monoxide Warnings

WARNING!

Carbon monoxide (CO) in exhaust gases is deadly.
Follow the precautions below to prevent carbon
monoxide poisoning:

• Do not inhale exhaust gases. They contain carbon

monoxide, a colorless and odorless gas which can kill.
Never run the engine in a closed area, such as a
garage, and never sit in a parked vehicle with the

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engine running for an extended period. If the vehicle is
stopped in an open area with the engine running for
more than a short period, adjust the ventilation system
to force fresh, outside air into the vehicle.

• Guard against carbon monoxide with proper mainte-

nance. Have the exhaust system inspected every time
the vehicle is raised. Have any abnormal conditions
repaired promptly. Until repaired, drive with all side
windows fully open.

• Keep the swing gate closed when driving your vehicle

to prevent carbon monoxide and other poisonous
exhaust gases from entering the vehicle.

FUEL FILLER CAP (GAS CAP)
The fuel cap is located on the left side of the vehicle. If the
fuel cap is lost or damaged, be sure the replacement cap
is for use with this vehicle.

Fuel Filler Cap Location

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CAUTION!

Damage to the fuel system or emission control
system could result from using an improper fuel cap
(gas cap). A poorly fitting cap could let impurities
into the fuel system. Also, a poorly fitting after-
market cap can cause the MIL (Malfunction Indica-
tor Light) to illuminate, due to fuel vapors escaping
from the system.

• Turn the engine off.
• Rotate the fuel cap to the left to remove.
• To replace the cap, insert it into the filler neck and

tighten the cap about 1/4 turn until you hear two
clicks. This is an indication that the cap is properly
tightened.

• Make sure that the fuel cap tether strap is not caught

under the fuel cap.

CAUTION!

To avoid fuel spillage and overfilling, do not “top
off” the fuel tank after filling.

NOTE:

When the fuel nozzle “clicks” or shuts off, the

fuel tank is full.

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WARNING!

• Remove the fuel cap (gas cap) slowly to prevent

fuel spray from the filler neck which may cause
injury.

• The volatility of some gasoline may cause a

buildup of pressure in the fuel tank that may
increase while you drive. This pressure can result
in a spray of gasoline and/or vapors when the cap
is removed from a hot vehicle. Removing the cap
slowly allows the pressure to vent and prevents
fuel spray.

• Never have any smoking materials lit in or near

the vehicle when the fuel cap is removed or the
tank filled.

• Never add fuel to the vehicle when the engine is

running.

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.

Locking Fuel Filler Cap (Gas Cap) — If Equipped

• Turn the engine off.
• Insert the ignition key into the fuel cap, and turn the

key to the right to unlock the fuel cap. Rotate the fuel
cap to the left to remove.

• To replace the cap, insert it into the filler neck and

tighten the cap about 1/4 turn until you hear two
clicks. This is an indication that the cap is properly
tightened.

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• Make sure that the fuel cap tether strap is not caught

under the fuel cap.

• Be sure to remove the key.

CAUTION!

To avoid fuel spillage and overfilling, do not “top
off” the fuel tank after filling.

NOTE:

When the fuel nozzle “clicks” or shuts off, the

fuel tank is full.

TRAILER TOWING
In this section you will find safety tips and information
on limits to the type of towing you can reasonably do
with your vehicle. Before towing a trailer carefully re-
view this information to tow your load as efficiently and
safely as possible.

To maintain warranty coverage, follow the requirements
and recommendations in this manual concerning ve-
hicles used for trailer towing.

Common Towing Definitions
The following trailer towing related definitions will assist
you in understanding the following information:

Gross Vehicle Weight Rating (GVWR)
The GVWR is the total allowable weight of your vehicle.
This includes driver, passengers, cargo and tongue
weight. The total load must be limited so that you do not
exceed the GVWR.

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Gross Trailer Weight (GTW)
The gross trailer weight (GTW) is the weight of the trailer
plus the weight of all cargo, consumables and equipment
(permanent or temporary) loaded in or on the trailer in its

⬙loaded and ready for operation⬙ condition. The recom-
mended way to measure GTW is to put your fully loaded
trailer on a vehicle scale. The entire weight of the trailer
must be supported by the scale.

Gross Combination Weight Rating (GCWR)
The gross combination weight rating (GCWR) is the total
permissible weight of your vehicle and trailer when
weighed in combination. (Note that GCWR ratings in-
clude a 150 lbs (68 kg) allowance for the presence of a
driver).

Gross Axle Weight Rating (GAWR)
The GAWR is the maximum capacity of the front and rear
axles. Distribute the load over the front and rear axles
evenly. Make sure that you do not exceed either front or
rear GAWR.

WARNING!

It is important that you do not exceed the maximum
front or rear GAWR. A dangerous driving condition
can result if either rating is exceeded. You could lose
control of the vehicle and have an accident.

Tongue Weight (TW)
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.

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Frontal Area
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
that typically provides adjustable friction associated with
the telescoping motion to dampen any unwanted 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. These kind of
hitches are the most popular on the market today and
they’re commonly used to tow small- and medium-sized
trailers.

Weight-Distributing Hitch
A weight-distributing hitch includes a receiver attached
to the tow vehicle, plus a removable hitch head and
spring bar assembly that fits into the receiver opening
and hook up brackets that connect the spring bars to the
trailer frame.

Trailer Hitch Classification
The rear bumper is intended to tow trailers up to 2,000
lbs (907 kg) without added equipment or alterations to
the standard equipment. Your vehicle may be factory
equipped for safe towing of trailers weighing over 2,000
lbs (907 kg) with the optional Trailer Tow Prep Package.
See your dealer for package content.

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.

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Refer to the Trailer Towing Weights (Maximum Trailer
Weight Ratings) chart for the Max. GTW towable for your
given drivetrain.

Trailer Hitch Classification

Class

Max. GTW (Gross Trailer

Wt.)

Class I - Light Duty

2,000 lbs (907 kg)

Class II - Medium
Duty

3,500 lbs (1 587 kg)

Class III - Heavy Duty

5,000 lbs (2 268 kg)

Class IV - Extra
Heavy Duty

10,000 lbs (4 540 kg)

All trailer hitches should be professionally installed on
your vehicle.

Trailer Towing Weights (Maximum Trailer Weight
Ratings)
The following chart provides the maximum trailer
weight ratings towable for your given drivetrain.

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Engine/

Transmis-

sion

Model

GVWR (Gross

Vehicle Wt. Rat-

ing)

GCWR (Gross

Combined Wt.

Rating)

Frontal Area

Max. GTW

(Gross Trailer

Wt.)

Max. Tongue

Wt. (See Note

1)

2.4L/

Manual

4,350 lbs (1 973

kg)

5,350 lbs (2 427

kg)

25 Sq. Ft.

(2.32 square

meters)

1,000 lbs (453

kg)

100 lbs (45 kg)

4.0L/All

4,250 lbs (1 928

kg)

6,250 lbs (2 835

kg)

25 Sq. Ft.

(2.32 square

meters)

2,000 lbs (907

kg)

200 lbs (91 kg)

4.0L/

Automatic

Unlim-

ited

4,600 lbs (2 086

kg)

8,100 lbs (3 674

kg)

32 Sq. Ft.

(2.97 square

meters)

3,500 lbs (1 587

kg)

350 lbs (159

kg)

Refer to local laws for maximum trailer towing speeds.

Note 1 – The trailer tongue weight must be considered as
part of the combined weight of occupants and cargo, and
should never exceed the weight referenced on the Tire
and Loading Information placard. Refer to the Tire–
Safety Information Section in this manual.

Trailer and Tongue Weight
Always load a trailer with 60% to 65% of the weight in
the front of the trailer. This places 10% to 15% of the
Gross Trailer Weight (GTW) on the tow hitch of your
vehicle. Loads balanced over the wheels or heavier in the
rear can cause the trailer to sway severely side to side

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