Toyota 4Runner: Tire information

Typical tire symbols

1. Tire size

2. Summer tire or all season tires An all season tire has “M+S” on the sidewall. A tire not marked “M+S” is a summer tire.

3. Uniform tire quality grading For details, see “Uniform Tire Quality Grading” that follows.

4. DOT and Tire Identification Number (TIN)

5. Tire ply composition and materials Plies are layers of rubber-coated parallel cords. Cords are the strands which form the plies in a tire.

6. Location of treadwear indicators

7. Load limit at maximum cold tire inflation pressure

8. Maximum cold tire inflation pressure This means the pressure to which a tire may be inflated.

9. TUBELESS or TUBE TYPE A tubeless tire does not have a tube and air is directly put into the tire. A tube type tire has a tube inside the tire and the tube maintains the air pressure.

10. Radial tires or bias-ply tires A radial tire has “RADIAL” on the sidewall. A tire not marked “RADIAL” is a bias-ply tire.

Typical DOT and Tire Identification Number (TIN)

1. DOT symbol*

2. Tire Identification Number (TIN)

3. Tire manufacturer’s identification mark

4. Tire size code

5. Manufacturer’s optional tire type code (3 or 4 letters)

6. Manufacturing week

7. Manufacturing year *: The DOT symbol certifies that the tire conforms to applicable Federal Motor Vehicle Safety Standards.

Tire size

Typical tire size information

The illustration indicates typical tire size.

1. Tire use (P = Passenger car, T = Temporary use)

2. Section width (millimeters)

3. Aspect ratio (tire height to section width)

4. Tire construction code (R = Radial, D = Diagonal)

5. Wheel diameter (inches)

6. Load index (2 digits or 3 digits)

7. Speed symbol (alphabet with one letter)

Tire dimensions

1. Section width

2. Tire height

3. Wheel diameter

Tire section names

1. Bead

2. Sidewall

3. Shoulder

4. Tread

5. Belt

6. Inner liner

7. Reinforcing rubber

8. Carcass

9. Rim lines

10. Bead wires

11. Chafer

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

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 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. Performance may differ 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.

Grade C corresponds to a level of performance which all passenger car tires must meet under the 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 of a tire assume that it is properly inflated and not overloaded.

Excessive speed, underinflation, or excessive loading, either separately or in combination, can cause heat buildup and possible tire failure.

Glossary of tire terminology