2010 GMC SIERRA width

Tire Terminology and Definitions
Air Pressure:The amount of air inside the tire
pressing outward on each square inch of the tire.
Air pressure is expressed in pounds per square
inch (psi) or kilopascal (kPa).
Accessory Weight
:This means the combined
weight of optional accessories. Some examples of
optional accessories are, automatic transmission,
power steering, power brakes, power windows,
power seats, and air conditioning.
Aspect Ratio
:The relationship of a tire's height
to its width.
Belt
:A rubber coated layer of cords that is
located between the plies and the tread. Cords
may be made from steel or other reinforcing
materials.
Bead
:The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the rim.
Bias Ply Tire
:A pneumatic tire in which the plies
are laid at alternate angles less than 90 degrees
to the centerline of the tread. Cold Tire Pressure
:The amount of air pressure
in a tire, measured in pounds per square inch (psi)
or kilopascals (kPa) before a tire has built up heat
from driving. See Inflation - Tire Pressure
on
page 6‑72
.
Curb Weight
:The weight of a motor vehicle with
standard and optional equipment including the
maximum capacity of fuel, oil, and coolant, but
without passengers and cargo.
DOT Markings
:A code molded into the sidewall
of a tire signifying that the tire is in compliance
with the U.S. Department of Transportation (DOT)
motor vehicle safety standards. The DOT code
includes the Tire Identification Number (TIN), an
alphanumeric designator which can also identify
the tire manufacturer, production plant, brand, and
date of production.
GVWR
:Gross Vehicle Weight Rating. See
Loading the Vehicle
on page 5‑30.
GAWR FRT
:Gross Axle Weight Rating for the
front axle. See Loading the Vehicle
on page 5‑30.
GAWR RR
:Gross Axle Weight Rating for the rear
axle. See Loading the Vehicle
on page 5‑30.
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Different Size Tires and Wheels
If you add wheels or tires that are a different size than
your original equipment wheels and tires, this could
affect the way your vehicle performs, including its
braking, ride and handling characteristics, stability, and
resistance to rollover. Additionally, if your vehicle has
electronic systems such as anti‐lock brakes, rollover
airbags, traction control, and electronic stability control,
the performance of these systems can be affected.
{WARNING:
If you add different sized wheels, your vehicle
may not provide an acceptable level of
performance and safety if tires not recommended
for those wheels are selected. You may increase
the chance that you will crash and suffer serious
injury. Only use GM specific wheel and tire
systems developed for your vehicle, and have
them properly installed by a GM certified
technician.
See Buying New Tires
on page 6‑83andAccessories
and Modificationson page 6‑4for additional
information.
Uniform Tire Quality Grading
Quality grades can be found where applicable on
the tire sidewall between tread shoulder and
maximum section width. For example:
Treadwear 200 Traction AA
Temperature A
The following information relates to the system
developed by the United States National
Highway Traffic Safety Administration (NHTSA),
which grades tires by treadwear, traction, and
temperature performance. This applies only to
vehicles sold in the United States. The grades are
molded on the sidewalls of most passenger car
tires. The Uniform Tire Quality Grading (UTQG)
system does not apply to deep tread, winter-type
snow tires, space-saver, or temporary use
spare tires, tires with nominal rim diameters of
10 to 12 inches (25 to 30 cm), or to some
limited-production tires.
6-85

It should be noted that the temperature grade for
this tire is established for a tire that is properly
inflated and not overloaded. Excessive speed,
underinflation, or excessive loading, either
separately or in combination, can cause heat
buildup and possible tire failure.
Wheel Alignment and Tire Balance
The tires and wheels on your vehicle were aligned and
balanced carefully at the factory to give you the longest
tire life and best overall performance. Adjustments to
wheel alignment and tire balancing will not be
necessary on a regular basis. However, if you notice
unusual tire wear or your vehicle pulling to one side or
the other, the alignment might need to be checked.
If you notice your vehicle vibrating when driving on a
smooth road, the tires and wheels might need to be
rebalanced. See your dealer/retailer for proper
diagnosis.
Wheel Replacement
Replace any wheel that is bent, cracked, or badly
rusted or corroded. If wheel nuts keep coming loose,
the wheel, wheel bolts and wheel nuts should be
replaced. If the wheel leaks air, replace it (except some
aluminum wheels, which can sometimes be repaired).
See your dealer/retailer if any of these conditions exist.
Your dealer/retailer will know the kind of wheel
you need.
Each new wheel should have the same load-carrying
capacity, diameter, width, offset and be mounted the
same way as the one it replaces.
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