miles (kilometers) at low speeds in the 3 hour period before the tire
pressure is measured or adjusted.
Curb weight
The weight of a motor vehicle with standard equipment including the
maximum capacity of fuel, oil, and coolant, air conditioner, and addi-
tional weight of optional equipment.
Extra load tire
A tire designed to operate at higher loads and at higher inflation pres-
sures than the corresponding standard tire.
Gross Axle Weight Rating (GAWR)
The load-carrying capacity of a single axle system, measured where
the tire contacts the ground.
Gross Vehicle Weight Rating (GVWR)
The maximum loaded weight of the vehicle.
Groove
The space between 2 adjacent tread ribs.
Load rating (code)
The maximum load that a tire is rated to carry for a given inflation
pressure. You may not find this information on all tires because it is
not required by law.
Maximum load rating
The load rating for a tire at the maximum permissible inflation pres-
sure for that tire.
Maximum loaded vehicle weight
The total of:
Curb weight.
Accessory weight.
Vehicle capacity weight.
Production options weight.
Maximum (permissible) inflation pressure
The maximum cold inflation pressure to which a tire may be inflated.
Also called “maximum inflation pressure.”
Recommended inflation pressure
The tire pressure recommended by the vehicle manufacturer for a tire
of a specified size that has not been driven for more than a couple of
miles (kilometers) at low speeds in the 3 hour period before the tire
pressure is measured or adjusted.
Reinforced tire
A tire designed to operate at higher loads and at higher inflation pres-
sures than the corresponding standard tire.
Rim
The outer edge of a wheel upon which the tire beads are seated.
Rim diameter
The nominal diameter of the wheel's tire bead seating surface. If you
change your wheel size, to wheels of a different diameter, you will
have to purchase new tires to match the new wheels.
Rim size
Designation means rim diameter and width.
Rim type designation
The industry or manufacturer's designation for a rim by style or code.
Rim width
The nominal distance between wheel rim flanges.
Section width
The linear distance between the exteriors of the sidewalls of an inflat-
ed tire, excluding elevations due to labeling decoration, or protective
bands.
Sidewall
The portion of a tire between the bead and the tread.
Sidewall separation
The parting of the rubber compound from the cord material in the
sidewall.
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 (Treadwear-value 150) would wear
one-and-one-half (1 1/2) 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
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 ⇒ .
Temperature
The temperature grades are A (the highest), B, and C representing
the tire's resistance to the generation of heat, and its ability to dissi-
pate heat when tested under controlled conditions on a specified in-
door laboratory test wheel.
Sustained high temperature can cause the material of the tire to de-
generate and reduce tire life, and excessive temperature can lead to
sudden tire failure.
The grade C corresponds to a level of performance which all passen-
ger car tires must meet under the Federal Motor Vehicle Safety
Standard No. 109. Grades B and A represent higher levels of perfor-
mance on the laboratory test wheel than the minimum required by law
⇒ .
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.