These indicators are molded into the bottom of the tread
grooves. They will appear as bands when the tread depth
becomes a 1/16 of an inch (2 mm). When the tread is
worn to the tread wear indicators, the tire should be
replaced. Refer to “Replacement Tires” in this section for
further information.
Life Of Tire
The service life of a tire is dependent upon varying
factors including, but not limited to:
•Driving style.
•Tire pressure - Improper cold tire inflation pressures
can cause uneven wear patterns to develop across the
tire tread. These abnormal wear patterns will reduce
tread life, resulting in the need for earlier tire replace-
ment.
•Distance driven.
•Performance tires, tires with a speed rating of V or
higher, and summer tires typically have a reduced
tread life. Rotation of these tires per the vehicle main-
tenance schedule is highly recommended.
WARNING!
Tires and the spare tire should be replaced after six
years, regardless of the remaining tread. Failure to
follow this warning can result in sudden tire failure.
You could lose control and have a collision resulting
in serious injury or death.
Keep dismounted tires in a cool, dry place with as little
exposure to light as possible. Protect tires from contact
with oil, grease, and gasoline.
618 STARTING AND OPERATING
Replacement Tires
The tires on your new vehicle provide a balance of many
characteristics. They should be inspected regularly for
wear and correct cold tire inflation pressures. The manu-
facturer strongly recommends that you use tires equiva-
lent to the originals in size, quality and performance
when replacement is needed. Refer to the paragraph on
“Tread Wear Indicator.” Refer to the Tire and Loading
Information placard or the Vehicle Certification Label for
the size designation of your tire. The Load Index and
Speed Symbol for your tire will be found on the original
equipment tire sidewall. See the Tire Sizing Chart ex-
ample found in the Tire Safety Information section of this
manual for more information relating to the Load Index
and Speed Symbol of a tire.
It is recommended to replace the two front tires or two
rear tires as a pair. Replacing just one tire can seriously
affect your vehicle’s handling. If you ever replace a
wheel, make sure that the wheel’s specifications match
those of the original wheels.
It is recommended you contact your authorized tire
dealer or original equipment dealer with any questions
you may have on tire specifications or capability. Failure
to use equivalent replacement tires may adversely affect
the safety, handling, and ride of your vehicle.5
STARTING AND OPERATING 619
WARNING!
•Do not use a tire, wheel size or rating other than
that specified for your vehicle. Some combinations
of unapproved tires and wheels may change sus-
pension dimensions and performance characteris-
tics, resulting in changes to steering, handling, and
braking of your vehicle. This can cause unpredict-
able handling and stress to steering and suspen-
sion components. You could lose control and have
a collision resulting in serious injury or death. Use
only the tire and wheel sizes with load ratings
approved for your vehicle.
•Never use a tire with a smaller load index or
capacity, other than what was originally equipped
on your vehicle. Using a tire with a smaller load
index could result in tire overloading and failure.
You could lose control and have a collision.
(Continued)
WARNING!(Continued)
•Failure to equip your vehicle with tires having
adequate speed capability can result in sudden tire
failure and loss of vehicle control.
CAUTION!
Replacing original tires with tires of a different size
may result in false speedometer and odometer read-
ings.
SUPPLEMENTAL TIRE PRESSURE INFORMATION —
IF EQUIPPED
A light load vehicle condition is defined as two passen-
gers [150 lbs (68 kg) each] plus 200 lbs (91 kg) of cargo.
Cold tire inflation pressures for a lightly loaded vehicle
will be found on the face of the driver’s door.
620 STARTING AND OPERATING
CAUTION!(Continued)
•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 truck. For example, if the spare is used to
replace an outer rear tire it will have to be re-
mounted on the rim so that the wheel is dished
inward. That way the tread design of asymmetrical
tires and the white writing of the OWL tires will
maintain proper position.
TIRE PRESSURE MONITOR SYSTEM (TPMS)
The Tire Pressure Monitor System (TPMS) will warn the
driver of a low tire pressure based on the vehicle recom-
mended cold placard pressure.
The tire pressure will vary with temperature by about 1
psi (7 kPa) for every 12°F (6.5°C). This means that when
the outside temperature decreases, the tire pressure will
decrease. Tire pressure should always be set based on
cold inflation tire pressure. This is defined as the tire
pressure after the vehicle has not been driven for at least
three hours, or driven less than 1 mile (1.6 km) after a
three hour period. The cold tire inflation pressure must
not exceed the maximum inflation pressure molded into
the tire sidewall. Refer to “Tires – General Information”
in “Starting and Operating” for information on how to
properly inflate the vehicle’s tires. The tire pressure will
also increase as the vehicle is driven - this is normal and
there should be no adjustment for this increased pres-
sure.
The TPMS will warn the driver of a low tire pressure if
the tire pressure falls below the low-pressure warning
limit for any reason, including low temperature effects
and natural pressure loss through the tire.
626 STARTING AND OPERATING
The TPMS will continue to warn the driver of low tire
pressure as long as the condition exists, and will not turn
off until the tire pressure is at or above the recommended
cold placard pressure. Once the low tire pressure warn-
ing (Tire Pressure Monitoring [TPM] Telltale Light) illu-
minates, you must increase the tire pressure to the
recommended cold placard pressure in order for the “Tire
Pressure Monitoring Telltale Light” to turn off. The
system will automatically update and the “Tire Pressure
Monitoring Telltale Light” will turn off once the system
receives the updated tire pressures. The vehicle may need
to be driven for up to 20 minutes above 15 mph
(25 km/h) in order for the TPMS to receive this informa-
tion.
For example, your vehicle may have a recommended
cold (parked for more than three hours) placard pressure
of 30 psi (207 kPa). If the ambient temperature is 68°F
(20°C) and the measured tire pressure is 27 psi (186 kPa),
a temperature drop to 20°F (-7°C) will decrease the tire
pressure to approximately 23 psi (158 kPa). This tire
pressure is sufficiently low enough to turn ON the “Tire
Pressure Monitoring Telltale Light.” Driving the vehicle
may cause the tire pressure to rise to approximately
27 psi (186 kPa), but the “Tire Pressure Monitoring
Telltale Light” will still be ON. In this situation, the “Tire
Pressure Monitoring Telltale Light” will turn OFF only
after the tires are inflated to the vehicle’s recommended
cold placard pressure value.
5
STARTING AND OPERATING 627
CAUTION!
•The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures and
warning have been established for the tire size
equipped on your vehicle. Undesirable system op-
eration or sensor damage may result when using
replacement equipment that is not of the same size,
type, and/or style. Aftermarket wheels can cause
sensor damage. Using aftermarket tire sealants may
cause the Tire Pressure Monitoring System (TPMS)
sensor to become inoperable. After using an after-
market tire sealant it is recommended that you take
your vehicle to your local dealer to have your
sensor function checked.
•After inspecting or adjusting the tire pressure,
always reinstall the valve stem cap. This will
prevent moisture and dirt from entering the valve
stem, which could damage the TPM sensor.
NOTE:
•The TPMS is not intended to replace normal tire care
and maintenance or to provide warning of a tire failure
or condition.
•The TPMS should not be used as a tire pressure gauge
while adjusting your tire pressure.
•Driving on a significantly under-inflated tire causes
the tire to overheat and can lead to tire failure.
Under-inflation also reduces fuel efficiency and tire
tread life, and may affect the vehicle’s handling and
stopping ability.
•The TPMS is not a substitute for proper tire mainte-
nance, and it is the driver ’s responsibility to maintain
correct tire pressure using an accurate tire pressure
gauge, even if under-inflation has not reached the level
to trigger illumination of the “Tire Pressure Monitor-
ing Telltale Light.”
628 STARTING AND OPERATING
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 EVIC/DID graphic) to the
vehicle’s recommended cold placard pressure inflation
value as shown in the#Inflate to XX#message. Once the
system receives the updated tire pressures, the system
will automatically update, the graphic display in the
EVIC/DID 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.
Service TPMS Warning
If a system fault is detected, the “Tire Pressure Monitor-
ing Telltale Light” will flash on and off for 75 seconds and
then remain on solid. The system fault will also sound a
chime. In addition, the EVIC/DID will display a#SER-
VICE TPM SYSTEM#message for a minimum of five
seconds and then display dashes (- -) in place of the
pressure value to indicate which sensor is not being
received.
“LOW TIRE PRESSURE” Message
630 STARTING AND OPERATING
Vehicles With Full Size Spare
1. The matching full size spare wheel and tire assembly
has a TPM sensor that can be monitored by the TPMS.
2. If you install the full size spare in place of a road tire
that has a pressure below the low-pressure warning
limit, upon the next ignition switch cycle, a chime will
sound and the “Tire Pressure Monitoring Telltale
Light” will turn ON. In addition, the EVIC/DID will
display a “LOW TIRE” message and a graphic show-
ing the low tire pressure value in a different color. An
#Inflate to XX#message will also be displayed.
3. After driving the vehicle for up to 20 minutes above
15 mph (25 km/h) the “Tire Pressure Monitoring
Telltale Light” will turn OFF and the pressure value
will be updated and return to it’s original color, as
long as no tire pressure is below the low-pressure
warning limit in any of the four active road tires.
Tire Pressure Information System (TPIS) 3500
Series Trucks
Your vehicle may be equipped with a Tire Pressure
Information System (TPIS).
The Tire Pressure Information System (TPIS) uses wire-
less technology with wheel rim mounted electronic sen-
sors to transmit tire pressure levels. Sensors mounted to
each wheel as part of the valve stem transmit tire
pressure readings to the receiver module.
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 TPIS consists of the following components:
•Receiver module
•Four TPM sensors (Single Rear Wheel (SRW) applica-
tions)
632 STARTING AND OPERATING