Dual wheel models require a special heavy-duty lug nut
tightening adapter (included with the vehicle) to correctly
tighten the lug nuts. Also, when it is necessary to remove
and install dual rear wheels, use a proper vehicle lifting
device.
NOTE:When installing a spare tire (if equipped) as part of
a dual rear wheel end combination, the tire diameter of the
two individual tires must be compared. If there is a
significant difference, the larger tire should be installed in
a front location. The correct direction of rotation for dual
tire installations must also be observed.
It is recommended that wheel stud nuts be kept torqued to
specifications at all times. Torque wheel stud nuts to
specifications at each lubrication interval.
Wheel Nuts
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 wheel nuts should first be firmly seated against the
wheel. The wheel nuts should then be tightened to recom-
mended torque. Tighten the wheel nuts to final torque in increments. Progress around the bolt circle, tightening the
wheel nut opposite to the wheel nut just previously
tightened until final torque is achieved.
To Stow The Flat Or Spare — If Equipped
Refer to Upfitters Body Builders Guide for information on
stowing your spare tire (if equipped).
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 recommended to
remove the caps.
For single rear wheel (SRW) models, use the flat blade on
the end of the lug wrench to pull the hub cap off. Insert the
blade end into the pull off notch and carefully pull the hub
cap off 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
342 IN CASE OF EMERGENCY
Hydraulic Brake Assist
The brake system power assist is provided by a hydro-
boost unit which shares fluid with the power steering
system. You may experience some clicking or hissing
noises from the hydro-boost system during hard braking
conditions.
NOTE:Under cold temperatures, pedal effort will be
higher than normal until the power steering fluid reaches
operating temperature.
WHEEL AND TIRE TORQUE SPECIFICATIONS
Proper lug nut/bolt torque is very important to ensure that
the wheel is properly mounted to the vehicle. Any time a
wheel has been removed and reinstalled on the vehicle, the
lug nuts/bolts should be torqued using a properly cali-
brated torque wrench using a high quality six sided (hex)
deep wall socket.
Torque Specifications
Lug Nut/
Bolt Torque Lug Nut/
Bolt Type **Lug Nut/
Bolt Size Lug Nut/
Bolt Socket Size
120-150 Ft- Lbs (160-
200 N·m) Cone M14 x 1.50 22 mm
130-160 Ft- Lbs (190-
220 N·m) Flanged
**Use only your authorized dealer recommended lug nuts/
bolts and clean or remove any dirt or oil before tightening.
Inspect the wheel mounting surface prior to mounting the
tire and remove any corrosion or loose particles.
9
TECHNICAL SPECIFICATIONS 425
Retighten the wheel nuts in the same sequence to the
torques listed in the table. Go through the sequence a
second time to verify that specific torque has been
achieved. Retighten to specifications after 25 miles (40 km)
and check the lug nut/bolt torque to be sure that all the lug
nuts/bolts are properly seated against the wheel.It is recommended that wheel stud nuts be kept torqued to
specifications at all times. Torque wheel stud nuts to
specifications at each lubrication interval.
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 wheel nuts should first be firmly seated against the
wheel. The wheel nuts should then be tightened to recom-
mended torque. Tighten the wheel nuts to final torque in
increments. Progress around the bolt circle, tightening the
wheel nut opposite to the wheel nut just previously
tightened until final torque is achieved.
WARNING!
To avoid the risk of forcing the vehicle off the jack, do
not tighten the lug nuts fully until the vehicle has been
lowered. Failure to follow this warning may result in
personal injury.
8/10 Lug Nuts/Bolts Torque Patterns
1 — 10 Bolt Pattern
2 — 8 Bolt Pattern
9
TECHNICAL SPECIFICATIONS 427
