Name of each section of tire




1. Bead

2. Sidewall

3. Shoulder

4. Tread

5. Belt

6. Inner liner

7. Reinforcing rubber

8. Carcass

9. Rim lines

10.Bead wires



—Uniform tire quality grading

This information has been prepared in accordance with regulations issued by the National Highway Traffic Safety Administration of the U.S. Department of Transportation. It provides the purchasers and/or prospective purchasers of Toyota vehicles with information on uniform tire quality grading.

Your Toyota dealer will help answer any questions you may have as you read this information.

DOT quality grades—All passenger vehicle tires must conform to Federal Safety Requirements in addition to these grades. 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.

Tread wear—The tread wear 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 (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 AA, A, B, C—The traction grades, from highest to lowest, are AA, A, B, and C, and they 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 braking (straight ahead) traction tests and does not include cornering (turning) traction.

Temperature A, B, C—The temperature grades are A (the highest), B, and C, representing the tire's resistance to the generation of heat and its ability to dissipate heat when tested under controlled conditions on a specified indoor laboratory test wheel. Sustained high temperature can cause the material of the tire to degenerate and reduce tire life, and excessive temperature can lead to sudden tire failure. The grade C corresponds to a level of performance which all passenger car tires must meet underthe Federal Motor Vehicle Safety Standard No. 109. Grades B and A represent higher levels of performance on the laboratory test wheel than the minimum required by law.

Warning: The temperature grades for this tire are established for a tire that is properly inflated and not overloaded. Excessive speed, underinfla-tion, orexcessive loading, eithersep-arately or in combination, can cause heat buildup and possible tire failure.

2007 YARIS HATCHBACK from Jan. '06 Prod. (QM52700U)

—Glossary of tire terminology

Tire related term


Cold tire inflation pressure

tire inflation pressure when the vehicle has been parked for at least 3 hours or more, or it has not been driven more than 1.5 km or 1 mile under that condition

Maximum inflation pressure

the maximum cold inflation pressure to which a tire may be inflated and it is shown on the sidewall of the tire

Recommended inflation pressure

cold tire inflation pressure recommended by a manufacturer

Accessory weight

the combined weight (in excess of those standard items which may be replaced) of automatic transmission, power steering, power brakes, power windows, power seats, radio, and heater, to the extent that these items are available as factory-installed equipment (whether installed or not)

Curb weight

the weight of a motor vehicle with standard equipment including the maximum capacity of fuel, oil, and coolant, and, if so equipped, air conditioning and additional weight optional engine

Maximum loaded vehicle weight

(b) accessory weight;

(c) vehicle capacity weight; and

(d) production options weight

Normal occupant weight

68 kg (150 lb.) times the number of occupants specified in the second column of Table 1 that follows

Tire related term


Production options weight

the combined weight of those installed regular production options weighing over 2.3 kg (5 lb.) in excess of those standard items which they replace, not previously considered in curb weight or accessory weight, including heavy duty brakes, ride levelers, roof rack, heavy duty battery, and special trim

Vehicle capacity weight (Total load capacity)

the rated cargo and luggage load plus 68 kg (150 lb.) times the vehicle's designated seating capacity

Intended outboard sidewall

(A) the sidewall that contains a whitewall, bears white lettering or bears manufacturer, brand, and/or model name molding that is higher or deeper than the same molding on the other sidewall of the tire, or

(B) the outward facing sidewall of an asymmetrical tire that has a particular side that must always face outward when mounted on a vehicle

Occupant distribution

distribution of occupants in a vehicle as specified in the third column of Table 1 that follows


a metal support for a tire or a tire and tube assembly upon which the tire beads are seated

Rim diameter (Wheel diameter)

nominal diameter of the bead seat

Rim size designation

rim diameter and width

Rim type designation

the industry of manufacturer's designation for a rim by style or code

Rim width

nominal distance between rim flanges

Vehicle maximum load on the tire

the load on an individual tire that is determined by distributing to each axle its share of the maximum loaded vehicle weight and dividing by two

Tire related term


Vehicle normal load on the tire

the load on an individual tire that is determined by distributing to each axle its share of the curb weight, accessory weight, and normal occupant weight (distributed in accordance with Table 1 that follows) and dividing by two

Weather side

the surface area of the rim not covered by the inflated tire

Table 1-Occupant loading and distribution for vehicle normal load for various designated seating capacities

Designated seating capacity, Number of occupants

Vehicle normal load, Number of occupants

Occupant distribution in a normally loaded vehicle

2 through 4


2 in front

5 through 10


2 in front, 1 in second seat

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