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, 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
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.
Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a speci®ed government test course.
For example, a tire graded 150 would wear one and
a half (1.5) 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 signi®cantly 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 speci®ed 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.
5-63
Cigarette Lighter.............................................3-17
Cleaning Aluminum Wheels..............................5-85
Cleaning Exterior Lamps/Lenses.......................5-83
Cleaning Fabric/Carpet....................................5-80
Cleaning Glass Surfaces..................................5-82
Cleaning Interior Plastic Components.................5-81
Cleaning Leather............................................5-81
Cleaning the Top of the Instrument Panel...........5-81
Cleaning the Windshield, Backglass and
Wiper Blades..............................................5-84
Cleaning Tires................................................5-85
Cleaning Vinyl................................................5-81
Cleaning........................................................5-80
Inside of Your Vehicle..................................5-80
Outside of Your Vehicle................................5-82
Underbody Maintenance...............................5-86
Weatherstrips..............................................5-82
Climate Control System...................................3-18
Air Filter, Passenger Compartment.................3-22
Outlet Adjustment........................................3-21
Clutch, Hydraulic.............................................5-27
Coinholder(s)..................................................2-35
Compact Disc Messages..................................3-42
Control of a Vehicle.......................................... 4-7
Convenience Net............................................2-37
Convertible Top..............................................2-40
Lowering and Raising the Canvas Top............2-43
Removing and Installing the Rear Window.........2-40
Removing and Installing the Side Window.........2-41Coolant.........................................................3-31
Engine Temperature Gage............................3-31
Heater, Engine............................................2-17
Cooling System..............................................5-33
Cruise Control.................................................. 3-9
Cupholder(s)..................................................2-35
Current and Past Model Order Forms................7-12
Customer Assistance Information........................ 7-8
Courtesy Transportation.................................. 7-8
Customer Assistance for Text Telephone
(TTY) Users.............................................. 7-4
Customer Assistance Offices........................... 7-4
Customer Satisfaction Procedure..................... 7-2
GM Mobility Program for Persons with
Disabilities................................................ 7-5
Reporting Safety Defects to General Motors......7-10
Reporting Safety Defects to the Canadian
Government............................................7-10
Reporting Safety Defects to the
United States Government.........................7-10
Roadside Assistance Program......................... 7-6
Service Publications Ordering Information........7-11
D
Daytime Running Lamps..................................3-13
Defensive Driving............................................. 4-3
Defogging and Defrosting.................................3-20
3
