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Dual Rear Wheels
The tires used on dual wheel assemblies should be
matched for wear to prevent overloading one tire in a set.
To check if tires are even, lay a straight edge across all
four tires. The straight edge should touch all the tires.
CAUTION!
3500/4500/5500 Dual Rear Tires have only one ap-
proved direction of rotation. This is to accommodate
the asymmetrical design (tread pattern) of the ON/
OFF road tire and the use of Outline White Letter
(OWL) tires.
²When replacing a flat, the spare tire may have to
be remounted on the rim or installed at a different
location to maintain the correct placement of the
tire on the wheel relative to the tire/wheel position
on the truck. For example, if the spare is used to
replace an outer rear tire it will have to be re-
mounted on the rim so that the wheel is dished
inward. That way the tread design of asymmetrical
tires and the white writing of the OWL tires will
maintain proper position.
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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.
Improper weight distributions can have an adverse effect
on the way your vehicle steers and handles and the way
the brakes operate.
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2. GTW
3. GAWR
4. 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 Ð Tires
þ
Do not attempt to tow a trailer while using a compact
spare tire.
þProper tire inflation pressures are essential to the safe
and satisfactory operation of your vehicle. Refer to the
Tires±General Information section of this manual on
Tire Pressures for proper tire inflation procedures.
þAlso, check the trailer tires for proper tire inflation
pressures before trailer usage.
þCheck for signs of tire wear or visible tire damage
before towing a trailer. Refer to the Tires±General
Information section of this manual on Tread Wear
Indicators for the proper inspection procedure.
þWhen replacing tires refer to the Tires±General Infor-
mation section of this manual on Replacement Tires 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 Ð Trailer Brakes
þ
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.
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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 tire's 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
(thumb wheel) by hand, it may be necessary to use the
jack drive tube in order to lower the jack.
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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.
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. 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 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.
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CAUTION!
The rear hub caps on the dual rear wheel has two pry
off notches. Make sure that the hook of the jack
handle driver is located squarely in the cap notch
before attempting to pull off.
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
lugnut 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 2 drops
of oil at the interface between the hex and the washer.
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Disc
WheelsType Nut Stud Size Torque
Ft. Lbs.Torque
Newton
Meters
Cone 9/16-18 120-150 160-200
Flanged 9/16-18 130-160 190-220
To Stow The Flat Or Spare (If Equipped)
Refer to Upfitters Body Builders Guide for information
on stowing your spare tire (If Equipped).
HOISTING
A conventional floor jack may be used at the jacking
locations, refer to the graphics that show jacking loca-
tions. However, a floor jack or frame hoist must never be
used on any other parts or the underbody.
CAUTION!
Never use a floor jack directly under the differential
housing of a loaded truck or damage to your vehicle
may result.
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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.
IF YOU NEED CONSUMER ASSISTANCE 507
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