Different Size Tires And Wheels; Uniform Tire Quality Grading - Chevrolet 2011 HHR Owner's Manual

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 different sized wheels are used, there may not
be an acceptable level of performance and safety
if tires not recommended for those wheels are
selected. This increases the chance of a crash
and serious injury. Only use GM specific wheel
and tire systems developed for the vehicle, and
have them properly installed by a GM certified
technician.
See Buying New Tires on page 6 65 and Accessories
and Modifications on page 6 3 for additional
information.
6-68

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.
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.
I n f o r ma t i o n P r o v i d e d b y :