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Please follow the table below for proper tire size, chain type, and axle recommendations:
VehicleAxle Recommendations Tire SizesChain Class
Chassis Cab 3500 (Single Rear Wheel) Models Rear Only
LT275/70R18E U Class
Chassis Cab 3500 (Dual
Rear Wheel) 4X2 Models Rear Only
LT235/80R17E U Class
Chassis Cab 3500 (Dual
Rear Wheel) 4X4 Models Front/Rear
LT235/80R17E U Class
Chassis Cab 4500/5500 Models Rear Only
225/70R19.5G U Class
WARNING!
Using tires of different size and type (M+S, Snow)
between front and rear axles can cause unpredictable
handling. You could lose control and have a collision.
CAUTION!
To avoid damage to your vehicle or tires, observe the
following precautions:
•Because of restricted traction device clearance be-
tween tires and other suspension components, it is
important that only traction devices in good condi-
tion are used. Broken devices can cause serious
damage. Stop the vehicle immediately if noise occurs
that could indicate device breakage. Remove the
damaged parts of the device before further use.
(Continued)
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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.
NOTE:If your vehicle is equipped with a Tire Pressure
Information System (TPIS):
• The Tire Pressure Information System (TPIS) uses
unique sensors in the inner rear wheels to help identify
them from the outer rear wheels, because of this, the
inner and outer wheel locations can’t be switched. •
After a tire rotation is completed, as shown below, the
system can auto learn the locations of each sensor ID.
Auto learning/localization occurs when the vehicle ig-
nition status is changed from Off to On and speeds of
greater than 5 mph (8km/h) are obtained and remain
over 5mph (8km/h) for at about a 15 minute period. You
may need to drive for 20 minutes to account slower
speeds and stops.
• If the tires are rotated incorrectly, the Auto localization of
the TPIS sensors will fail to locate correctly resulting in
incorrect locations for the pressure values displayed in
the Instrument Cluster.
CAUTION!
• 4500/5500 Dual Rear Tires may only have one ap-
proved direction of rotation. This is to accommodate
the asymmetrical design (tread pattern) of the On/
Off road tire.
• When 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 vehicle. For example, if the spare is used to
(Continued)
Tire Rotation
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CAUTION!(Continued)
replace an outer rear tire it will have to be remounted
on the rim so that the wheel is dished inward. That
way the tread design of asymmetrical tires will
maintain proper position.
DEPARTMENT OF TRANSPORTATION UNIFORM
TIRE QUALITY GRADES
The following tire grading categories were established
by the National Highway Traffic Safety Administration.
The specific grade rating assigned by the tire’s manu-
facturer in each category is shown on the sidewall of the
tires on your vehicle.
All passenger vehicle tires must conform to Federal
safety requirements in addition to these grades.
Treadwear
The Treadwear grade is a comparative rating, based on
the wear rate of the tire when tested under controlled
conditions on a specified government test course. For
example, a tire graded 150 would wear one and one-half
times as well on the government course as a tire graded
100. The relative performance of tires depends upon the
actual conditions of their use, however, and may depart significantly from the norm due to variations in driving
habits, service practices, and differences in road charac-
teristics and climate.
Traction Grades
The Traction grades, from highest to lowest, are AA, A,
B, and C. These grades represent the tire’s ability to stop
on wet pavement, as measured under controlled condi-
tions on specified government test surfaces of asphalt
and concrete. A tire marked C may have poor traction
performance.
WARNING!
The traction grade assigned to this tire is based on
straight-ahead braking traction tests, and does not
include acceleration, cornering, hydroplaning, or
peak traction characteristics.
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.
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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 pas-
senger vehicle tires must meet under the Federal Motor
Vehicle Safety Standard No. 109. Grades B and A
represent 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.
STORING THE VEHICLE
If you are storing your vehicle for more than 21 days, we
recommend that you take the following steps to minimize
the drain on your vehicle’s battery:
• Disconnect the negative cable from battery.
• Any time you store your vehicle or keep it out of service
(i.e., vacation) for two weeks or more, run the air
conditioning system at idle for about five minutes in the fresh air and high blower setting. This will ensure
adequate system lubrication to minimize the possibility
of compressor damage when the system is started again.
BODYWORK
Protection From Atmospheric Agents
Vehicle body care requirements vary according to geo-
graphic locations and usage. Chemicals that make roads
passable in snow and ice and those that are sprayed on
trees and road surfaces during other seasons are highly
corrosive to the metal in your vehicle. Outside parking,
which exposes your vehicle to airborne contaminants, road
surfaces on which the vehicle is operated, extreme hot or
cold weather and other extreme conditions will have an
adverse effect on paint, metal trim, and underbody protec-
tion.
The following maintenance recommendations will enable
you to obtain maximum benefit from the corrosion resis-
tance built into your vehicle.
What Causes Corrosion?
Corrosion is the result of deterioration or removal of paint
and protective coatings from your vehicle.
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Special Care
•If you drive on salted or dusty roads or if you drive near
the ocean, hose off the undercarriage at least once a
month.
• It is important that the drain holes in the lower edges of
the doors, rocker panels, and trunk be kept clear and
open.
• If you detect any stone chips or scratches in the paint,
touch them up immediately. The cost of such repairs is
considered the responsibility of the owner.
• If your vehicle is damaged due to a collision or similar
cause that destroys the paint and protective coating,
have your vehicle repaired as soon as possible. The cost
of such repairs is considered the responsibility of the
owner.
• If you carry special cargo such as chemicals, fertilizers,
de-icer salt, etc., be sure that such materials are well
packaged and sealed.
• If a lot of driving is done on gravel roads, consider mud
or stone shields behind each wheel.
• Use Mopar Touch Up Paint on scratches as soon as
possible. Your authorized dealer has touch up paint to
match the color of your vehicle.
INTERIORS
Seats And Fabric Parts
Use Mopar Total Clean to clean fabric upholstery and
carpeting.
WARNING!
Do not use volatile solvents for cleaning purposes.
Many are potentially flammable, and if used in closed
areas they may cause respiratory harm.
Stain Repel Fabric Cleaning Procedure — If
Equipped
Stain Repel seats may be cleaned in the following manner:
• Remove as much of the stain as possible by blotting with
a clean, dry towel.
• Blot any remaining stain with a clean, damp towel.
• For tough stains, apply Mopar Total Clean, or a mild
soap solution to a clean, damp cloth and remove stain.
Use a fresh, damp towel to remove soap residue.
• For grease stains, apply Mopar Multi-Purpose Cleaner
to a clean, damp cloth and remove stain. Use a fresh,
damp towel to remove soap residue.
• Do not use any harsh solvents or any other form of
protectants on Stain Repel products.8
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TECHNICAL SPECIFICATIONS
CONTENTS
IDENTIFICATION DATA ...................424
▫ Vehicle Identification Number .............424
BRAKE SYSTEM ....................... .424
▫ Hydraulic Brake Assist ...................425
WHEEL AND TIRE TORQUE SPECIFICATIONS . .425
▫ Torque Specifications ....................425
FUEL REQUIREMENTS ...................428
▫ 6.4L Engine .......................... .428
▫ Reformulated Gasoline ..................428
▫ Materials Added To Fuel .................428 ▫
Gasoline/Oxygenate Blends ...............429
▫ Do Not Use E-85 In Non-Flex Fuel Vehicles . . . .429
▫ CNG And LP Fuel System Modifications ......430
▫ MMT In Gasoline ...................... .430
▫ Fuel System Cautions ....................430
▫ Carbon Monoxide Warnings ...............431
FLUID CAPACITIES ..................... .432
FLUIDS AND LUBRICANTS ................433
▫ Engine ............................. .433
▫ Chassis ............................ .435
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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.
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TECHNICAL SPECIFICATIONS 425
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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). Do not oil wheel studs. For chrome wheels, do not substi-
tute with chrome plated wheel nuts.
Oil Interface Location
Wheel Mounting Surface
426 TECHNICAL SPECIFICATIONS