Page 294 of 475

2. Economy—
Improper inflation pressures can cause uneven wear
patterns to develop across the tire tread. These abnormal
wear patterns will reduce tread life resulting in a need for
earlier tire replacement. Under inflation, also increases
tire rolling resistance and results in higher fuel consump-
tion.
3. Ride Comfort and Vehicle Stability—
Proper tire inflation contributes to a comfortable ride.
Over inflation produces a jarring and uncomfortable ride.
Tire Inflation Pressures
The proper cold tire inflation pressure is listed either on
the face of the driver’s door or on the driver’s side “B”
pillar.
Some vehicles may have Supplemental Tire Pressure
Information for vehicle loads that are less than themaximum loaded vehicle condition. These pressure con-
ditions will be found in the “Supplemental Tire Pressure
Information” section of this manual.
The pressure should be checked and adjusted as well as
inspecting for signs of tire wear or visible damage at least
once a month. Use a good quality pocket-type gauge to
Tire Placard Location
294 STARTING AND OPERATING
Page 295 of 475

check tire pressure. Do not make a visual judgement
when determining proper inflation. Radial tires may look
properly inflated even when they are under inflated.
CAUTION!
After inspecting or adjusting the tire pressure, al-
ways reinstall the valve stem cap (if equipped). This
will prevent moisture and dirt from entering the
valve stem, which could damage the valve stem.
Inflation pressures specified on the placard are always
“cold tire inflation pressure.” Cold tire inflation pressure
is defined as the tire pressure after the vehicle has not
been driven for at least 3 hours, or driven less than 1 mile
(1 km) after a 3 hour period. The cold tire inflation
pressure must not exceed the maximum inflation pres-
sure molded into the tire sidewall.Check tire pressures more often if subject to a wide range
of outdoor temperatures, as tire pressures vary with
temperature changes.
Tire pressures change by approximately 1 psi (7 kPa) per
12° F (7° C) of air temperature change. Keep this in mind
when checking tire pressure inside a garage, especially in
the winter.
Example: If garage temperature = 68° F (20° C) and the
outside temperature = 32° F (0° C) then the cold tire
inflation pressure should be increased by 3 psi (21 kPa),
which equals 1 psi (7 kPa) for every 12° F (7° C) for this
outside temperature condition.
Tire pressure may increase from 2 to 6 psi (13 to 40 kPa)
during operation. DO NOT reduce this normal pressure
build up or your tire pressure will be too low.
STARTING AND OPERATING 295
5
Page 296 of 475
Tire Pressures for High Speed Operation
The manufacturer advocates driving at safe speeds
within posted speed limits. Where speed limits or condi-
tions are such that the vehicle can be driven at high
speeds, maintaining correct tire inflation pressure is very
important. Increased tire pressure and reduced vehicle
loading may be required for high-speed vehicle opera-
tion. Refer to original equipment or an authorized tire
dealer for recommended safe operating speeds, loading
and cold tire inflation pressures.WARNING!
High speed driving with your vehicle under maxi-
mum load is dangerous. The added strain on your
tires could cause them to fail. You could have a
serious accident. Don’t drive a vehicle loaded to the
maximum capacity at continuous speeds above 75
mph (120 km/h).
296 STARTING AND OPERATING
Page 299 of 475

WARNING!
The limited use spare tires are for emergency use
only. Installation of this limited use spare tire affects
vehicle handling. With this tire, do not drive more
than 60 mph (100 km/h). Keep inflated to the cold
tire inflation pressure listed on either your tire
placard or limited use spare tire and wheel assembly.
Replace (or repair) the original tire at the first
opportunity and reinstall it on your vehicle. Failure
to do so could result in loss of vehicle control.
Tire Spinning
When stuck in mud, sand, snow, or ice conditions, do not
spin your vehicle’s wheels above 35 mph (55 km/h).
Refer to the paragraph on “Freeing A Stuck Vehicle” in
Section 6 of this manual.
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 30 mph (48 km/h) for more than 30 seconds
continuously when you are stuck, and don’t let
anyone near a spinning wheel, no matter what the
speed.
STARTING AND OPERATING 299
5
Page 300 of 475
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. They will appear as bands when the tread depth
becomes 1/16 inch (2 mm). When the tread is worn to the
tread wear indicators, the tire should be replaced.
Many states have laws requiring tire replacement at this
point.
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
300 STARTING AND OPERATING
Page 301 of 475

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 dismounted 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 (refer to the paragraph on“Tread Wear Indicators”). Refer to the “Tire and Loading
Information” 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, handling, and ride of your vehicle. We recommend
that you contact your original equipment or an autho-
rized tire dealer with any questions you may have on tire
specifications or capability.
STARTING AND OPERATING 301
5
Page 303 of 475

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.
SUPPLEMENTAL TIRE PRESSURE INFORMATION
– IF EQUIPPED
A light load vehicle condition is defined as two passen-
gers {150 lbs (68 kg) each} plus 200 lbs (91kg) of cargo.
Cold tire inflation pressures for a lightly loaded vehicle
will be found on the face of the driver’s door.
TIRE CHAINS
Use “Class S” chains on your vehicle, or other traction
aids that meet SAE Type “S” specifications.
NOTE:Chains must be the proper size for the vehicle,
as recommended by the chain manufacturer.
CAUTION!
To avoid damage to your vehicle, tires or chains, observe the
following precautions:
•Because of limited chain clearance between tires and other
suspension components, it is important that only chains in
good condition are used. Broken chains can cause serious
vehicle damage. Stop the vehicle immediately if noise occurs
that could suggest chain breakage. Remove the damaged parts
of the chain before further use.
•Install chains as tightly as possible and then retighten after
driving about 1/2 mile (0.8 km).
•Do not exceed 45 mph (72 km/h).
•Drive cautiously and avoid severe turns and large bumps,
especially with a loaded vehicle.
•Do not install tire chains on front wheels of 4x2 vehicles.
•Do not drive for a prolonged period on dry pavement.
•Observe the tire chain manufacturer’s instructions on method
of installation, operating speed, and conditions for usage.
Always use the lower suggested operating speed of the chain
manufacturer if different than the speed recommended by the
manufacturer.
STARTING AND OPERATING 303
5
Page 304 of 475

These cautions apply to all chain traction devices, includ-
ing link and cable (radial) chains.
Tire chain use is permitted only on the rear tires of your
truck.
NOTE:The use of class “S” chains is permitted on your
vehicle with P245/70R17 tires.
CAUTION!
Do not use tire chains on 4x4 trucks equipped with
tires other than P245/70R17 tires. There may not be
adequate clearance for the chains and you are risking
structural or body damage to your vehicle. Do not
use tire chains on the 4X2 front wheels of your
vehicle. There may not be adequate clearance for the
chains and you are risking structural or body dam-
age to your vehicle.
SNOW TIRES
Snow tires should be of the same size and type construc-
tion as the front tires. Consult the manufacturer of the
snow tire to determine any maximum vehicle speed
requirement associated with the tire. These tires should
always be operated at the vehicle maximum capacity
inflation pressures under any load condition.
While studded tires improve performance on ice, skid
and traction capability on wet or dry surfaces may be
poorer than that of non-studded tires. Some states pro-
hibit studded tires; therefore, local laws should be
checked before using these tire types.
304 STARTING AND OPERATING