|
|
|
READING YOUR TIRE
UTQG
Ply Rating vs. Load Range
Ply ratings and load ranges identify load and inflation
limits of a given tire size when used in a specific type
of service.
- Ply ratings: An older method of rating load capacity,
these are listed as 4-ply, 6-ply, 8-ply, etc.
- Load ratings: The current method of rating a tire's
load-carrying capacity is denoted by letters (B, C, D, E, etc.).
|
Uniform Tire Quality Grade (UTQG) Labeling
Required by the government, the UTQG provides comparative
manufacturer information. Tires are subjected to a series of
government-mandated tests that measure performance in treadwear,
traction and temperature resistance. All testing is done by the
tire manufacturer.
|
Treadwear
Treadwear is a measurement of tread durability. Tested against
an industry standard, the assigned numerical grade indicates how
well the tread lasts compared with a reference standard of 100. A
treadwear rating 200 means the tread wears twice as well as the
standard. Actual wear depends on the conditions under which the
tire is used. Driving habits, service practices, differences in
road surface and varying climates all affect treadwear.
|
|
Traction
Traction is a measurement of a tire's ability to stop on wet test
surfaces of asphalt and concrete under controlled conditions.
Traction grades are assigned by the UTQG system and branded on the
sidewall. Traction grade
is determined only for straight-ahead, wet braking on concrete and
asphalt. It doesn't include cornering, which may also be an
important customer performance need.
- Traction Grade A: The tire performed well on both surfaces.
- Traction Grade B: The tire performed well on at least one
of the surfaces.
- Traction Grade C: The tire performed poorly on one or
both of the surfaces.
|
|
Temperature Resistance
The UTQG also provides a measure of resistance to heat generation
under normal operating conditions. The test is conducted under
predetermined standards for inflation and loading. Excessive speed,
underinflation and overloading can all cause adverse heat build-up.
Sustained high temperatures can reduce tire durability. Resistance
grades are branded on the sidewall.
- Resistance Grade A: The maximum performance level
indicating the tire withstood a half-hour run at 115 mph
without failing.
- Resistance Grade B: The tire passed 100 mph but not 115 mph.
- Resistance Grade C: The minimum performance level
indicating that the tire failed to complete a half-hour at
100 mph.
|
|
Department of Transportation (DOT) Certification
"DOT" is branded on the tire's sidewall indicating the tire is
certified by the Department of Transportation. Following the DOT
branding is a serial number designating the tire manufacturer,
manufacturing plant, tire size and date of manufacture. Federal
law requires that tire dealers record the DOT identification
numbers along with the tire buyer's name and address.
|
|
Additional Tire Labeling Conventions
Mud and Snow Labeling
If a tire is rated for safe performance in mud and snow, it will
be noted on the sidewall of the tire with either M/S, M+S or M&S.
A tire is certified under the definitions set forth by the Rubber
Manufacturers Association (RMA).
|
|
Tire Construction Labeling
Tread ply and sidewall ply information, including tire ply
composition and materials used, must also be identified. An
example would be: Tread: 2 Plies Rayon + 4 Plies Fiberglass
Sidewall: 2 Plies Rayon
|
|
 |
|
|
|
|
|
|