Page 221 of 448

▫Tire Inflation Pressures.................269
▫Radial-Ply Tires......................271
▫Compact Spare Tire — If Equipped.........272
▫Limited Use Spare — If Equipped.........273
▫Tire Spinning........................273
▫Tread Wear Indicators..................274
▫Replacement Tires.....................275
▫Alignment And Balance.................276
Supplemental Tire Pressure Information.......276
Tire Chains...........................276
Snow Tires...........................278
Tire Rotation Recommendations............279
▫Dual Rear Wheels.....................280
Engine Runaway.......................281Fuel Requirements......................281
▫Adding Fuel.........................282
▫Bulk Fuel Storage.....................284
▫Fuel Specifications....................284
Vehicle Loading........................286
▫Certification Label.....................286
Trailer Towing.........................289
▫Definitions..........................289
▫Axle Lubricant And Trailer Towing.........291
▫Trailer Towing Recommendations..........291
▫Trailer Towing — Hitches...............292
▫Connecting Trailer Lighting And Electric
Trailer Brakes........................293
▫Trailer Weight And Trailer Tongue Weight....294
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Page 260 of 448

TIRE SAFETY INFORMATION
Tire Markings
NOTE:
•P(Passenger)-Metric tire sizing is based on U.S. design
standards. P-Metric tires have the letter “P” molded
into the sidewall preceding the size designation. Ex-
ample: P215/65R15 95H.
•European Metric tire sizing is based on European
design standards. Tires designed to this standard have
the tire size molded into the sidewall beginning with
the section width. The letterPis absent from this tire
size designation. Example: 215/65R15 96H
•LT(Light Truck)-Metric tire sizing is based on U.S.
design standards. The size designation for LT-Metric
tires is the same as for P-Metric tires except for the
letters “LT” that are molded into the sidewall preced-
ing the size designation. Example: LT235/85R16.
•Temporary Spare tires are high pressure compact
spares designed for temporary emergency use only.
Tires designed to this standard have the letter “T”
molded into the sidewall preceding the size designa-
tion. Example: T145/80D18 103M.
•High Flotation tire sizing is based on U.S. design
standards and begins with the tire diameter molded
into the sidewall. Example: 31x10.5 R15 LT.
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Tire Sizing Chart
EXAMPLE:
Size Designation:
P= Passenger car tire size based on U.S. design standards
....blank....= Passenger car tire based on European design standards
LT= Light Truck tire based on U.S. design standards
T= Temporary Spare tire
31= Overall Diameter in Inches (in)
215= Section Width in Milimeters (mm)
65= Aspect Ratio in Percent (%)
—Ratio of section height to section width of tire.
10.5= Section Width in Inches (in)
R= Construction Code
—Rmeans Radial Construction.
—Dmeans Diagonal or Bias Construction.
15= Rim Diameter in Inches (in)
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Page 265 of 448

Tire and Loading Information Placard
This placard tells you important information about the:
1) number of people that can be carried in the vehicle
2) the total weight your vehicle can carry
3) the tire size designed for your vehicle
4) the cold tire inflation pressures for the front, rear
and spare tires.
Loading
The vehicle maximum load on the tire must not exceed
the load carrying capacity of the tire on your vehicle. You
will not exceed the tire’s load carrying capacity if you
adhere to the loading conditions, tire size and cold tire
inflation pressures specified on the Tire and Loading
Information placard and the Vehicle Loading section of
this manual.
NOTE:Under a maximum loaded vehicle condition,
gross axle weight ratings (GAWR’s) for the front and rear
axles must not be exceeded. For further information on
GAWR’s, vehicle loading and trailer towing, see the
Vehicle Loading section of this manual.
To determine the maximum loading conditions of your
vehicle, locate the statement “The combined weight of
occupants and cargo should never exceed XXX kg or XXX
lbs.” on the Tire and Loading Information placard. The
Tire and Loading Information
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Page 272 of 448

Compact Spare Tire — If Equipped
The compact spare is for temporary emergency use with
radial tires. It is engineered to be used on your style
vehicle only. Since this tire has limited tread life, the
original tire should be repaired (or replaced) and rein-
stalled at the first opportunity.
WARNING!
Temporary use spare tires are for emergency use
only. With these tires, do not drive more than 50 mph
(80 km/h). Temporary-use spare tires have limited
tread life. When two or more tread wear indicators
appear in adjacent grooves, the temporary use spare
tire needs to be replaced. Be sure to follow the
warnings which apply to your spare. Failure to do so
could result in spare tire failure and loss of vehicle
control.
Do not install a wheel cover or attempt to mount a
conventional tire on the compact spare wheel, since the
wheel is designed specifically for the compact spare.
Do not install more than one compact spare tire/wheel
on the vehicle at any given time.
CAUTION!
Because of the reduced ground clearance, do not take
your vehicle through an automatic car wash with the
compact spare installed. Damage to the vehicle may
result.
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Limited Use Spare — If Equipped
The limited use spare tire is for temporary emergency use
on your vehicle. This tire is identified by a limited use
spare tire warning label located on the limited use spare
tire and wheel assembly. This tire may look like the
original equipped tire on the front or rear axle of your
vehicle, but it is not. Installation of this limited use spare
tire affects vehicle handling. Since it is not the same tire,
replace (or repair) the original tire and reinstall on vehicle
at the first opportunity.WARNING!
The limited use spare tires are for emergency use
only. Installation of this limited use spare tire affects
vehicle handling. With this tire, do not drive more
than 60 mph (100 km/h). Keep inflated to the cold
tire inflation pressure listed on either your tire
placard or limited use spare tire and wheel assembly.
Replace (or repair) the original tire at the first
opportunity and reinstall it on your vehicle. Failure
to do so could result in loss of vehicle control.
Tire Spinning
When stuck in mud, sand, snow, or ice conditions, do not
spin your vehicle’s wheels above 35 mph (55 km/h).
See the paragraph on Freeing A Stuck Vehicle in Section
6 of this manual.
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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 Dual Rear Tires have only one approved direc-
tion of rotation. This is to accommodate the asym-
metrical design (tread pattern) of the ON/OFF road
tire and the use of Outline White Letter (OWL) tires.
•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 posi-
tion on the truck. For example, if the spare is used
to 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 asymmetri-
cal tires and the white writing of the OWL tires
will maintain proper position.
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WHAT TO DO IN EMERGENCIES
CONTENTS
Hazard Warning Lights..................314
Adding Fuel — 24–Valve Cummins Turbo
Diesel...............................315
Jack Location..........................316
▫All Models..........................316
Changing A Flat Tire....................317
▫Removing The Spare Tire................317
▫Tire Changing Procedure................318
Hoisting.............................327Jump-Starting.........................327
▫With Portable Starting Unit..............330
Freeing A Stuck Vehicle..................331
Emergency Tow Hooks — If Equipped........331
Towing A Disabled Vehicle................332
▫4-Wheel- Drive Vehicles.................332
▫2–Wheel- Drive Vehicles................333
6