396 IN CASE OF EMERGENCY
Dual Rear Wheels
Slots in the wheels will assist in properly orienting the inner
and outer wheels. Align these slots when assembling 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.
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 loca -
tion. The correct direction of rotation for dual tire installa -
tions must also be observed
It is recommended that wheel stud nuts be kept torqued to
specifications at all times. Torque wheel stud nuts to specifi -
cations at each lubrication interval.
Refer to “Wheel And Tire Torque Specifications” in “Tech -
nical Specifications” for further information. Wheel Nuts
All wheel nuts should be tightened occasionally to eliminate
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 recommended
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.
Refer to “Wheel And Tire Torque Specifications” in “Tech -
nical Specifications” for further information.
To Stow The Flat Or Spare — If Equipped
Refer to Upfitters Body Builder’s Guide for information on
stowing your spare tire (if equipped).
476 TECHNICAL SPECIFICATIONS
BRAKE SYSTEM
If power assist is lost for any reason (for example, repeated
brake applications with the engine off), the brakes will still
function. However, you will experience a substantial
increase in braking effort to stop the vehicle.
If either the front or rear hydraulic system loses normal
braking capability, the remaining system will still function
with some loss of overall braking effectiveness. This will be
evident by increased pedal travel during application, greater
pedal force required to slow or stop, and activation of the
“Brake Warning Light” and the “ABS Warning Light” (if
equipped) during brake use.
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. 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 calibrated
torque wrench using a high quality six sided (hex) deep wall
socket.
TECHNICAL SPECIFICATIONS 477
Torque Specifications
**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.
NOTE:
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. Ensure that the
socket is fully engaged on the lug nut/bolt (do not insert it
half way). Oil Interface Location
Do not oil wheel studs. For chrome wheels, do not substitute
with chrome plated wheel nuts.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
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478 TECHNICAL SPECIFICATIONS
Wheel Mounting Surface
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. 8/10 Lug Nuts/Bolts Torque Patterns
It is recommended that wheel stud nuts be kept torqued to
specifications at all times. Torque wheel stud nuts to specifi -
cations at each lubrication interval.
All wheel nuts should be tightened occasionally to eliminate
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. 1 — 10 Bolt Pattern
2 — 8 Bolt Pattern
TECHNICAL SPECIFICATIONS 479
The wheel nuts should then be tightened to recommended
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.
FUEL REQUIREMENTS
6.4L Engine
Do not use E-85 flex fuel or ethanol blends greater than 15%
in this engine.
This engines is designed to meet all emissions regu -
lations and provide satisfactory fuel economy and
performance when using high quality unleaded
gasoline having a posted octane number range of 87 to 89 as
specified by the (R+M)/2 method. The use of 89 octane
“Plus” gasoline is recommended for optimum performance
and fuel economy. While operating on gasoline with an octane number of 87,
hearing a light knocking sound from the engine is not a cause
for concern. However, if the engine is heard making a heavy
knocking sound, see your dealer immediately. Use of gaso -
line with an octane number lower than 87 can cause engine
failure and may void or not be covered by the New Vehicle
Limited Warranty.
Poor quality gasoline can cause problems such as hard
starting, stalling, and hesitations. If you experience these
symptoms, try another brand of gasoline before considering
service for the vehicle.
Reformulated Gasoline
Many areas of the country require the use of cleaner burning
gasoline referred to as “Reformulated Gasoline”. Reformu -
lated gasoline contains oxygenates and are specifically
blended to reduce vehicle emissions and improve air quality.
The use of reformulated gasoline is recommended. Properly
blended reformulated gasoline will provide improved
performance and durability of engine and fuel system
components.WARNING!
To avoid the risk of forcing the vehicle off the jack, do
not tighten the lug nuts/bolts fully until the vehicle has
been lowered. Failure to follow this warning may result
in personal injury.
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