Page 430 of 516

Black plate (64,1)Chevrolet Volt Owner Manual - 2011
10-64 Vehicle Care
GM's exclusive TPC Spec
system considers over a dozen
critical specifications that impact
the overall performance of the
vehicle, including brake system
performance, ride and handling,
traction control, and tire pressure
monitoring performance. GM's TPC
Spec number is molded onto the
tire's sidewall near the tire size.
If the tires have an all‐season
tread design, the TPC spec number
will be followed by MS, for mud
and snow. SeeTire Sidewall
Labeling on page 10‑49 for
additional information.
GM recommends replacing all the
tires at the same time. Uniform
tread depth on all tires will help
to maintain the performance of
the vehicle. Braking and handling
performance may be adversely
affected if all the tires are not
replaced at the same time.
See Tire Inspection on page 10‑61
and Tire Rotation on page 10‑61 for
information on proper tire rotation.{WARNING
Tires could explode during
improper service. Attempting to
mount or dismount a tire could
cause injury or death. Only your
dealer or authorized tire service
center should mount or dismount
the tires.
{WARNING
Mixing tires of different sizes,
brands, or types may cause
loss of control of the vehicle,
resulting in a crash or other
vehicle damage. Use the
correct size, brand, and type
of tire on all wheels.
{WARNING
Using bias-ply tires on the
vehicle may cause the wheel
rim flanges to develop cracks
after many miles of driving.
A tire and/or wheel could fail
suddenly and cause a crash.
Use only radial-ply tires with
the wheels on the vehicle.
If the vehicle tires must be replaced
with a tire that does not have a TPC
Spec number, make sure they are
the same size, load range, speed
rating, and construction (radial) as
the original tires.
Vehicles that have a tire pressure
monitoring system could give an
inaccurate low‐pressure warning
if non‐TPC Spec rated tires are
installed. See Tire Pressure Monitor
System on page 10‑55.
Page 432 of 516

Black plate (66,1)Chevrolet Volt Owner Manual - 2011
10-66 Vehicle Care
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.
While the tires available on
General Motors passenger
cars and light trucks may vary
with respect to these grades,
they must also conform to
federal safety requirements and
additional General Motors Tire
Performance Criteria (TPC)
standards.
All Passenger Car Tires Must
Conform to Federal Safety
Requirements In Addition
To These Grades.Treadwear
The treadwear grade is a
comparative rating based
on the wear rate of the tire
when tested under controlled
conditions on a specified
government test course.
For example, a tire graded
150 would wear one and a
half (1½) times as well on
the government course as
a tire graded 100. The relative
performance of tires depends
upon the actual conditions of
their use, however, and may
depart significantly from the
norm due to variations in
driving habits, service practices
and differences in road
characteristics and climate.
Traction
–AA, A, B, C
The traction grades, from
highest to lowest, are AA, A, B,
and C. Those grades represent
the tire's ability to stop on
wet pavement as measured
under controlled conditions
on specified government
test surfaces of asphalt and
concrete. A tire marked C may
have poor traction performance.
Warning: The traction grade
assigned to this tire is based
on straight-ahead braking
traction tests, and does not
include acceleration, cornering,
hydroplaning, or peak traction
characteristics.
Page 435 of 516

Black plate (69,1)Chevrolet Volt Owner Manual - 2011
Vehicle Care 10-69
Used Replacement Wheels
{WARNING
Replacing a wheel with a used
one is dangerous. How it has
been used or how far it has been
driven may be unknown. It could
fail suddenly and cause a crash.
When replacing wheels, use a
new GM original equipment
wheel.
Tire Chains
{WARNING
Do not use tire chains. There is
not enough clearance. Tire chains
used on a vehicle without the
proper amount of clearance can
cause damage to the brakes,
suspension or other vehicle(Continued)
WARNING (Continued)
parts. The area damaged by
the tire chains could cause
loss of control and a crash.
Use another type of traction
device only if its manufacturer
recommends it for the vehicle's
tire size combination and
road conditions. Follow that
manufacturer's instructions.
To avoid vehicle damage, drive
slow and readjust or remove the
traction device if it contacts the
vehicle. Do not spin the wheels.
If traction devices are used,
install them on the front tires.
If a Tire Goes Flat
This vehicle has a tire sealant and
compressor kit. SeeTire Sealant
and Compressor Kit on page 10‑71.
There is no spare tire, no tire
changing equipment, and no
place to store a tire.
To properly lift this vehicle, see
Lifting the Vehicle on page 10‑5.
It is unusual for a tire to blowout
while driving, especially if the
tires are maintained properly.
See Tires on page 10‑48.
If air goes out of a tire, it is much
more likely to leak out slowly.