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These indicators are molded into the bottom of the tread
grooves. They will appear as bands when the tread depth
becomes 1/16 in (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
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 a collision resulting 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
334 STARTING AND OPERATING
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WARNING! (Continued)
•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 a collision result-
ing in serious injury or death.
•Failure to equip your vehicle with tires having
adequate speed capability can result in sudden tire
failure and loss of vehicle control resulting in
serious injury or death.
CAUTION!
Replacing original tires with tires of a different size
may result in false speedometer and odometer read-
ings.
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 (91 kg) 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 U” chains or other traction aids that meet SAE
Type “U” 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:
(Continued)
336 STARTING AND OPERATING
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•On 4X2 vehicles, class “U” snow chains are permitted
on the rear wheels only of vehicles equipped with
LT245/70R17, LT265/70R17, and LT235/80R17 size
tires.
•On 4X4 Single Rear Wheel (SRW) vehicles, class “U”
snow chains are permitted on the rear wheels only on
vehicles equipped with LT265/70R17.
CAUTION!
Do not use tire chains on the 4X2 front wheels of
SRW (Single Rear Wheels) equipped with LT245/
70R17, LT265/70R17 tires or 4X4 front tires of vehicles
equipped with LT265/70R17 tires. There may not be
adequate clearance for the chains and you are risking
structural or body damage to your vehicle.
SNOW TIRES
Some areas of the country require the use of snow tires
during the winter. All season tires can be identified by the
M+S designation on the tire sidewall.
If you need snow tires, select tires equivalent in size and
type to the original equipment tires. Use snow tires only
in sets of four; failure to do so may adversely affect the
safety and handling of your vehicle.
Snow tires generally have lower speed ratings than what
was originally equipped with your vehicle and should
not be operated at sustained speeds over 75 mph
(120 km/h). For speeds above 75 mph (120 km/h) refer to
original equipment or an authorized tire dealer for
recommended safe operating speeds, loading and cold
tire inflation pressures.
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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 and cargo.
The label also specifies maximum 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.
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Towing Requirements – Tires
•
Do not attempt to tow a trailer with less than the full
size spare tire.
•Proper tire inflation pressures are essential to the safe
and satisfactory operation of your vehicle. Refer to
“Tires – General Information” in “Starting and Oper-
ating” for proper tire inflation procedures.
•Check the trailer tires for proper tire inflation pres-
sures before trailer usage.
•Check for signs of tire wear or visible tire damage
before towing a trailer. Refer to “Tires – General
Information” in “Starting and Operating” for the
proper inspection procedure.
•When replacing tires, refer to “Tires – General Infor-
mation” in “Starting and Operating” for proper tirereplacement procedures. Replacing tires with a higher
load carrying capacity will not increase the vehicle’s
GVWR and GAWR limits.
Towing Requirements – Trailer Brakes
•
Donotinterconnect the hydraulic brake system or
vacuum system of your vehicle with that of the trailer.
This could cause inadequate braking and possible
personal injury.
•An electronically actuated trailer brake controller is
required when towing a trailer with electronically
actuated brakes. When towing a trailer equipped with
a hydraulic surge actuated brake system, an electronic
brake controller is not required.
•Trailer brakes are recommended for trailers over
1,000 lbs (454 kg) and required for trailers in excess of
2,000 lbs (907 kg).
5
STARTING AND OPERATING 357
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8. Lower the jack to its fully closed position. If the jack
will not lower by turning the dial (thumbwheel) by hand,
it may be necessary to use the jack drive tube in order to
lower the jack. Stow the replaced tire, jack, and tools as
previously described.
9. Adjust the tire pressure when possible.
NOTE:Do not oil wheel studs. For chrome wheels, do
not substitute with chrome plated wheel nuts.
Hub Caps/Wheel Covers — If Equipped
The hub caps must be removed before raising the vehicle
off the ground.
CAUTION!
Use extreme caution when removing the front and
rear center caps. Damage can occur to the center cap
and/or the wheel if screwdriver type tools are used. A
pulling motion, not a pry off motion, is recom-
mended to remove the caps.
For single rear wheel (SRW) models, use the blade on the
end of the lug wrench to pry the hub cap off. Insert the
blade end into the pry off notch and carefully pop off the
hub cap with a back and forth motion.
On 3500 models with dual rear wheels (DRW), you must
first remove the hub caps. The jack handle driver has a
hook at one end that will fit in the pry off notch of the
rear hub caps. Position the hook and pull out on the
ratchet firmly. The hub cap should pop off. The wheel
skins can now be removed. For the front hub cap on
6
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FREEING A STUCK VEHICLE
If the vehicle becomes stuck in snow, sand, or mud, it can
often be moved by a rocking motion. Move the shift lever
rhythmically between DRIVE/1st and REVERSE while
applying slight pressure to the accelerator.
CAUTION!
•Racing the engine or spinning the wheels may
lead to transmission overheating and failure. Al-
low the engine to idle with the shift lever in
NEUTRAL for at least one minute after every five
rocking-motion cycles. This will minimize over-
heating and reduce the risk of transmission failure
during prolonged efforts to free a stuck vehicle.
(Continued)
CAUTION! (Continued)
•When “rocking” a stuck vehicle by moving be-
tween DRIVE/1st and REVERSE, do not spin the
wheels faster than 15 mph (24 km/h), or drivetrain
damage may result.
•Revving the engine or spinning the wheels too fast
may lead to transmission overheating and failure.
It can also damage the tires. Do not spin the
wheels above 30 mph (48 km/h) while in gear (no
transmission shifting occurring).
396 WHAT TO DO IN EMERGENCIES
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Check the coolant recovery bottle tubing for brittle rub-
ber, cracking, tears, cuts and tightness of the connection
at the bottle and radiator. Inspect the entire system for
leaks.
With the engine at normal operating temperature (but
not running), check the cooling system pressure cap for
proper vacuum sealing by draining a small amount of
engine coolant (antifreeze) from the radiator drain cock.
If the cap is sealing properly, the engine coolant (anti-
freeze) will begin to drain from the coolant recovery
bottle. DO NOT REMOVE THE COOLANT PRESSURE
CAP WHEN THE COOLING SYSTEM IS HOT.
Cooling System – Drain, Flush, And Refill
If the engine coolant (antifreeze) is dirty or contains a
considerable amount of sediment, clean and flush with a
reliable cooling system cleaner. Follow with a thorough
rinsing to remove all deposits and chemicals. Properly
dispose of old engine coolant (antifreeze) solution.Refer to the “Maintenance Schedule” for the proper
maintenance intervals.
Selection Of Coolant
Use only the manufacturer’s recommended engine cool-
ant (antifreeze). Refer to “Fluids, Lubricants, and Genu-
ine Parts” in “Maintaining Your Vehicle” for further
information.
CAUTION!
•Mixing of engine coolant (antifreeze) other than
specified HOAT engine coolant (antifreeze), may
result in engine damage and may decrease corro-
sion protection. If a non-HOAT engine coolant
(antifreeze) is introduced into the cooling system
in an emergency, it should be replaced with the
specified engine coolant (antifreeze) as soon as
possible.
(Continued)
422 MAINTAINING YOUR VEHICLE