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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.
Loading
The actual total weight and the weight of the front and
rear of your vehicle at the ground can best be determined
by weighing it when it is loaded and ready for operation.
The entire vehicle should first be weighed on a commer-
cial scale to insure that the GVWR has not been exceeded.
The weight on the front and rear of the vehicle should
then be determined separately to be sure that the load is
properly distributed over front and rear axle. Weighing
the vehicle may show that the GAWR of either 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.
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WARNING! (Continued)
4. Trailer tongue weight rating for the trailer hitch
utilized (This requirement may limit the ability to
always achieve the 10% to 15% range of tongue
weight as a percentage of total trailer weight).
Towing Requirements – Tires
•
Do not attempt to tow a trailer while using a compact
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 Operat-
ing” 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 Infor-
mation” in “Starting and Operating” for the proper
inspection procedure.
•When replacing tires, refer to “Tires–General Informa-
tion” in “Starting and Operating” for proper tire
replacement procedures. Replacing tires with a higher
load carrying capacity will not increase the vehicle’s
GVWR and GAWR limits.
Towing Requirements – Trailer Brakes
•
Donot interconnect 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
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WARNING! (Continued)
•To assure that spare tires, flat or inflated, are
securely stowed, spares must be stowed with the
valve stem facing the ground.
•Turn on the Hazard Warning flasher.
1. If equipped, remove the spare wheel, jack, and tools
from storage.
2. Using the wheel wrench, loosen, but do not remove,
the wheel nuts by turning them counterclockwise one
turn while the wheel is still on the ground. 3. When changing the front wheel, assemble the jack
drive tube to the jack and connect the drive tube to the
extension tube. Place the jack under the axle as close to
the tire as possible with the drive tubes extending to the
front. Connect the jack tube extension and wheel wrench.
Jack Warning Label
Front Jacking Locations
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When changing a rear wheel, assemble the jack drive
tube to the jack and connect the drive tube to the
extension tube. Securely place the jack under the sway
bar bracket (unless both tires are flat on one side, then
place jack under shock bracket) facing forward in vehicle.
Connect the jack tube extension and lug wrench.Before raising the wheel off the ground, make sure that
the jack will not damage surrounding truck parts and
adjust the jack position as required.
NOTE:
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.
4. By rotating the wheel wrench clockwise, raise the
vehicle until the wheel just clears the surface.
WARNING!
Raising the vehicle higher than necessary can make
the vehicle unstable and cause an accident. It could
slip off the jack and hurt someone near it. Raise the
vehicle only enough to remove the tire.
Rear Jacking Location
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5. Remove the wheel nuts and pull the wheel off. Install
the spare wheel and wheel nuts with the cone shaped end
of the nuts toward the wheel on single rear wheel (SRW)
models. On dual rear wheel models (DRW) the lug nuts
are a two-piece assembly with a flat face. Lightly tighten
the nuts. To avoid risk of forcing the vehicle off the jack,
do not fully tighten the nuts until the vehicle has been
lowered.
6. Using the wheel wrench, finish tightening the nuts
using a crisscross pattern. The correct nut tightness is
135 ft lbs (183 N·m) torque for single rear wheel (SRW)
models and 145 ft lbs (197 N·m) for dual rear wheel
models. If in doubt about the correct tightness, have them
checked with a torque wrench by your authorized dealer
or at a service station.WARNING!
A loose tire or jack thrown forward in a collision or
hard stop could injure someone in the vehicle. Al-
ways stow the jack parts and the extra tire and wheel
in the places provided.
7. Install wheel center cap (if equipped) and remove
wheel blocks. Do not install chrome or aluminum wheel
center caps on the spare wheel. This may result in cap
damage.
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.
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You must use the flat end of the lug wrench to pry off the
wheel skins. Insert the flat tip completely and using a
back and forth motion, loosen the wheel skin. Repeat this
procedure around the tire until the skin pops off.
Replace the wheel skins first using a rubber mallet. When
replacing the hub caps, tilt the cap retainer over the lug
nut bolt circle and strike the high side down with a
rubber mallet. Be sure that the hub caps and wheel skins
are firmly seated around the wheel.
Dual Rear Wheels
Dual wheels are flat mounted, center piloted. The lug
nuts are a two-piece assembly. When the tires are being
rotated or replaced, clean these lug nuts and add two
drops of oil at the interface between the hex and the
washer.Slots in the wheels will assist in properly orienting the
inner and outer wheels. Align these slots when assem-
bling the wheels for best access to the tire valve on the
inner wheel. The tires of both dual wheels must be
completely off the ground when tightening to insure
wheel centering and maximum wheel clamping.
Oiling Location
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Wheel Nut Torque
All wheel nuts should be tightened occasionally to elimi-
nate the possibility of wheel studs being sheared or the
bolt holes in the wheels becoming elongated. This is
especially important during the first few hundred miles/
kilometers of operation to allow the wheel nuts to
become properly set. All nuts should first be firmlyseated against the wheel. The nuts should then be
tightened to recommended torque. Tighten the nuts to
final torque in increments. Progress around the bolt
circle, tightening the nut opposite to the nut just previ-
ously tightened until final torque is achieved. Recom-
mended torques are shown in the following chart.
Disc Wheels Type Nut
Stud SizeTorque Ft Lbs Torque Newton
Meters
Cone 9/16-18120-150160-200
Flanged 9/16-18130-160190-220
To Stow The Flat Or Spare — If Equipped
Refer to Upfitters Body Builders Guide for information
on stowing your spare tire (if equipped).
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Temperature Grades
The temperature grades are A (the highest), B, and C,
representing the tire’s resistance to the generation of heat
and its ability to dissipate heat, when tested under
controlled conditions on a specified indoor laboratory
test wheel. Sustained high temperature can cause the
material of the tire to degenerate and reduce tire life, and
excessive temperature can lead to sudden tire failure. The
grade C corresponds to a level of performance, which all
passenger car tires must meet under the Federal Motor
Vehicle Safety Standard No. 109. Grades B and A repre-
sent higher levels of performance on the laboratory test
wheel, than the minimum required by law.WARNING!
The temperature grade for this tire is established for
a tire that is properly inflated and not overloaded.
Excessive speed, under-inflation, or excessive load-
ing, either separately or in combination, can cause
heat buildup and possible tire failure.
456 IF YOU NEED CONSUMER ASSISTANCE