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NOTE:It is particularly important for you to check the tire
pressure in all of the tires on your vehicle monthly and to
maintain the proper pressure.
The TPMS consists of the following components:
• Receiver module
• Four TPM sensors
• Various TPMS messages, which display in the instru-
ment cluster
• TPM Telltale Light
Tire Pressure Monitoring Low Pressure Warnings
The “Tire Pressure Monitoring Telltale Light” will
illuminate in the instrument cluster and a chime
will sound when tire pressure is low in one or more of the
four active road tires. In addition, the instrument cluster
will display a “LOW TIRE” message and a graphic show-
ing the pressure values of each tire with the low tire
pressure values in a different color. An Inflate to XX
message will also be displayed. Should this occur, you should stop as soon as possible and
inflate the tires with a low pressure condition (those in a
different color in the instrument cluster graphic) to the
vehicle’s recommended cold placard pressure inflation
value as shown in the
Inflate to XXmessage. Once the
system receives the updated tire pressures, the system will
automatically update, the graphic display in the instru-
ment cluster will return to it’s original color, and the “Tire
Pressure Monitoring Telltale Light” will turn off. The
vehicle may need to be driven for up to 20 minutes above
15 mph (24 km/h) in order for the TPMS to receive this
information.
“LOW TIRE PRESSURE” Message
5
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Gross Vehicle Weight Rating (GVWR)
The GVWR is the total permissible weight of your vehicle
including driver, passengers, vehicle, options and cargo.
The label also specifies maximum capacities of front and
rear axle systems (GAWR). Total load must be limited so
GVWR and front and rear GAWR are not exceeded.
Payload
The payload of a vehicle is defined as the allowable load
weight a truck can carry, including the weight of the driver,
all passengers, options and cargo.
Gross Axle Weight Rating (GAWR)
The GAWR is the maximum permissible load on the front
and rear axles. The load must be distributed in the cargo
area so that the GAWR of each axle is not exceeded.
Each axle GAWR is determined by the components in the
system with the lowest load carrying capacity (axle,
springs, tires or wheels). Heavier axles or suspension
components sometimes specified by purchasers for in-
creased durability does not necessarily increase the vehi-
cle’s GVWR.
Tire Size
The tire size on the Vehicle Certification Label represents
the actual tire size on your vehicle. Replacement tires must
be equal to the load capacity of this tire size.
Rim Size
This is the rim size that is appropriate for the tire size
listed.
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.
550 STARTING AND OPERATING
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Towing Requirements — Tires
•Do not attempt to tow a trailer while using a compact
spare tire.
• Proper tire inflation pressures are essential to the safe
and satisfactory operation of your vehicle. Refer to
“Tires – General Information” in “Starting And Operat-
ing” for proper tire inflation procedures.
• Check the trailer tires for proper tire inflation pressures
before trailer usage.
• Check for signs of tire wear or visible tire damage before
towing a trailer. Refer to “Tires – General Information”
in “Starting And Operating” for the proper inspection
procedure.
• When replacing tires, refer to “Tires – General Informa-
tion” in “Starting And Operating” for proper tire re-
placement procedures. Replacing tires with a higher
load carrying capacity will not increase the vehicle’s
GVWR and GAWR limits.
Towing Requirements — Trailer Brakes
WARNING!
• Do not connect trailer brakes to your vehicle’s hy-
draulic brake lines. It can overload your brake sys-
tem and cause it to fail. You might not have brakes
when you need them and could have an accident.
• Towing any trailer will increase your stopping dis-
tance. When towing you should allow for additional
space between your vehicle and the vehicle in front
of you. Failure to do so could result in an accident.
CAUTION!
If the trailer weighs more than 1,000 lbs (453 kg)
loaded, it should have its own brakes and they should
be of adequate capacity. Failure to do this could lead to
accelerated brake lining wear, higher brake pedal
effort, and longer stopping distances.
5
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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 lug nut/bolt and the
washer. Do not oil wheel studs.
Inspect the wheel mounting surface prior to mounting the
tire and remove any corrosion or loose particles.
Two-Piece Lug NutWheel Mounting Surface
582 WHAT TO DO IN EMERGENCIES
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Jack Instructions (1500 Series)
WARNING!
Carefully follow these tire changing warnings to help
prevent personal injury or damage to your vehicle:
•Always park on a firm, level surface as far from the
edge of the roadway as possible before raising the
vehicle.
• Turn on the Hazard Warning flasher.
• Block the wheel diagonally opposite the wheel to be
raised.
• Set the parking brake firmly and set an automatic
transmission in PARK; a manual transmission in
REVERSE.
• Never start or run the engine with the vehicle on a
jack.
• Do not let anyone sit in the vehicle when it is on a
jack.
• Do not get under the vehicle when it is on a jack. If
you need to get under a raised vehicle, take it to a
service center where it can be raised on a lift.
• Only use the jack in the positions indicated and for
lifting this vehicle during a tire change.
(Continued)
WARNING! (Continued)
•If working on or near a roadway, be extremely
careful of motor traffic.
• To assure that spare tires, flat or inflated, are securely
stowed, spares must be stowed with the valve stem
facing the ground.
Jack Warning Label
6
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Page 598 of 734
9. Adjust the tire pressure when possible.
NOTE:Do not oil wheel studs. For chrome wheels, do not
substitute with chrome plated wheel nuts.
To Stow The Flat Or Spare
NOTE: Vehicles equipped with aluminum wheels cannot
be stored under the vehicle because the wheel retainer will
not fit through the wheel pilot hole. Secure the flat tire in
the bed of the truck. Have the flat tire repaired or replaced
immediately.
WARNING!
A loose tire thrown forward in a collision or hard stop
could injure the occupants in the vehicle. Have the
deflated (flat) tire repaired or replaced immediately. 1. Turn the wheel so that the valve stem is facing the
ground and toward the rear of the vehicle for conve-
nience in checking the spare tire inflation. Slide the
wheel retainer through the center of the wheel.
Reinstalling The Retainer
596 WHAT TO DO IN EMERGENCIES
Page 610 of 734
WARNING!(Continued)
•If working on or near a roadway, be extremely
careful of motor traffic.
• To assure that spare tires, flat or inflated, are securely
stowed, spares must be stowed with the valve stem
facing the ground.
CAUTION!
Do not attempt to raise the vehicle by jacking on
locations other than those indicated in the Jacking
Instructions for this vehicle.
Jack Warning Label
Lug Wrench Adaptor Shown In Jack And Tools Assembly
608 WHAT TO DO IN EMERGENCIES
Page 613 of 734

Connect the jack tube extension and wheel wrench.
CAUTION!
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 bottle jack will not lower by turning the dial
(thumbwheel) by hand, it may be necessary to use the jack
drive tube in order to lower the jack.
4. By rotating the wheel wrench clockwise, raise the ve- hicle until the wheel just clears the surface.
WARNING!
Raising the vehicle higher than necessary can make the
vehicle unstable. 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. On single rear-wheel (SRW) trucks, install the spare wheel and
wheel nuts with the cone shaped end of the wheel nuts
toward the wheel. On 3500 dual rear-wheel models
(DRW) trucks, if the outer tire is being replaced then leave the inner wheel on the vehicle. If the inner wheel
is being replaced remove the outer wheel and replace
the inner wheel. The wheel nuts are a two-piece assem-
bly with a flat face. Lightly tighten the wheel nuts. To
avoid the risk of forcing the vehicle off the jack, do not
fully tighten the wheel nuts until the vehicle has been
lowered.
Rear Inner Wheel Proper Placement
(Dual Rear Wheel Equipped)
6
WHAT TO DO IN EMERGENCIES 611