
Radial Ply Tire:A pneumatic tire in which the
ply cords that extend to the beads are laid at
90 degrees to the centerline of the tread.
Rim:A metal support for a tire and upon which
the tire beads are seated.
Sidewall:The portion of a tire between the tread
and the bead.
Speed Rating:An alphanumeric code assigned
to a tire indicating the maximum speed at
which a tire can operate.
Traction:The friction between the tire and the
road surface. The amount of grip provided.
Tread:The portion of a tire that comes into
contact with the road.
Treadwear Indicators:Narrow bands, sometimes
called wear bars, that show across the tread of
a tire when only 1/16 inch (1.6 mm) of tread
remains. SeeWhen It Is Time for New Tires on
page 523.UTQGS (Uniform Tire Quality Grading
Standards):A tire information system that
provides consumers with ratings for a tire’s
traction, temperature, and treadwear. Ratings are
determined by tire manufacturers using
government testing procedures. The ratings are
molded into the sidewall of the tire. SeeUniform
Tire Quality Grading on page 527.
Vehicle Capacity Weight:The number of
designated seating positions multiplied by 150 lbs
(68 kg) plus the rated cargo load. SeeLoading
Your Vehicle on page 407.
Vehicle Maximum Load on the Tire:Load on an
individual tire due to curb weight, accessory
weight, occupant weight, and cargo weight.
Vehicle Placard:A label permanently attached to
a vehicle showing the vehicle’s capacity weight
and the original equipment tire size and
recommended in ation pressure. See “Tire and
Loading Information Label” underLoading
Your Vehicle on page 407.
514

For additional information and details about the
DIC operation and displays seeDIC Operation and
Displays (With DIC Buttons) on page 261orDIC
Operation and Displays (Without DIC Buttons)
on page 267andDIC Warnings and Messages on
page 270.
You may notice, during cooler weather conditions,
that the tire pressure monitor light, located on
the instrument panel cluster, and the CHECK TIRE
PRESSURE message will appear when the
vehicle is rst started and then turn off as you
start to drive the vehicle. This could be an early
indicator that the tire pressures are getting low and
need to be in ated to the proper pressure.
Each tire, including the spare (if provided), should
be checked monthly when cold and in ated to
the in ation pressure recommended by the vehicle
manufacturer on the vehicle placard or tire
in ation pressure label. (If your vehicle has tires of
a different size than the size indicated on the
vehicle placard or tire in ation pressure label, you
should determine the proper tire in ation
pressure for those tires.)As an added safety
feature, your vehicle has
been equipped with a
tire pressure monitoring
system (TPMS) that
illuminates a low tire
pressure telltale when
one or more of your tires
is signi cantly
under-in ated.
Accordingly, when the low tire pressure telltale
illuminates, you should stop and check your tires
as soon as possible, and in ate them to the
proper pressure. Driving on a signi cantly
under-in ated tire causes the tire to overheat and
can lead to tire failure. Under-in ation also
reduces fuel efficiency and tire tread life, and may
affect the vehicle’s handling and stopping ability.
Please note that the TPMS is not a substitute for
proper tire maintenance, and it is the driver’s
responsibility to maintain correct tire pressure, even
if under-in ation has not reached the level to trigger
illumination of the TPMS low tire pressure telltale.
517

Your vehicle has also been equipped with a TPMS
malfunction indicator to indicate when the
system is not operating properly. The TPMS
malfunction indicator is combined with the low tire
pressure telltale. When the system detects a
malfunction, the telltale will ash for approximately
one minute and then remain continuously
illuminated. This sequence will continue upon
subsequent vehicle start-ups as long as the
malfunction exists.
When the malfunction indicator is illuminated, the
system may not be able to detect or signal low
tire pressure as intended. TPMS malfunctions may
occur for a variety of reasons, including the
installation of replacement or alternate tires or
wheels on the vehicle that prevent the TPMS from
functioning properly. Always check the TPMS
malfunction telltale after replacing one or more
tires or wheels on your vehicle to ensure that the
replacement or alternate tires and wheels allow
the TPMS to continue to function properly.The CHECK TIRE PRESSURE warning message
and low tire pressure light (telltale) will come
on each time the vehicle is started until the tires
are in ated to the correct in ation pressure.
The Tire and Loading Information label (tire
information placard) shows the size of your
vehicle’s original tires and the correct in ation
pressure for your vehicle’s tires when they
are cold. SeeIn ation - Tire Pressure on
page 515. For the location of the tire and loading
information label, seeLoading Your Vehicle
on page 407.
Your vehicle’s TPMS can alert you about a low
tire pressure condition but it does not replace
normal tire maintenance. SeeTire Inspection and
Rotation on page 521andTires on page 507.
Notice:Do not use a tire sealant if your
vehicle has Tire Pressure Monitors. The liquid
sealant can damage the tire pressure monitor
sensors.
518

When It Is Time for New Tires
One way to tell when it
is time for new tires is
to check the treadwear
indicators, which will
appear when your tires
have only 1/16 inch
(1.6 mm) or less of tread
remaining. Some
commercial truck tires
may not have treadwear
indicators.You need a new tire if any of the following
statements are true:You can see the indicators at three or more
places around the tire.
You can see cord or fabric showing through
the tire’s rubber.
The tread or sidewall is cracked, cut or
snagged deep enough to show cord or fabric.
The tire has a bump, bulge, or split.
The tire has a puncture, cut, or other damage
that cannot be repaired well because of the
size or location of the damage.
523