Toyota Tacoma (N400, 2024-2026) Owner's Manual: Tire Sizes, Load Ratings and Identification

Typical tire symbols

Full-size tire

Temporary spare tire

1. Tire size designation shown on the tire sidewall
2. DOT marking and Tire Identification Number (TIN)
3. Location of the treadwear indicators molded into the tire
4. Tire ply composition and the materials used in its construction

Plies are structural layers made from parallel cords coated with rubber. The cords are the individual reinforcing strands that form each ply and contribute to the tire's overall strength.

5. Radial tires or bias-ply tires
   A radial tire carries the word "RADIAL" on its sidewall. If the tire does not display the "RADIAL" marking, it is classified as a bias-ply tire.
6. TUBELESS or TUBE TYPE
   A tubeless tire contains no separate inner tube, so the air is retained directly inside the tire and wheel assembly. A tube-type tire contains an inner tube that holds the inflation pressure.
7. Load limit at maximum cold tire inflation pressure (P.535), indicating the maximum load permitted under the stated cold-pressure condition
8. Maximum cold tire inflation pressure
   This marking identifies the maximum pressure to which the tire may be inflated when cold.
9. Uniform tire quality grading
   Refer to the "Uniform Tire Quality Grading" section below for an explanation of the applicable treadwear, traction, and temperature ratings.
10. Summer tires or all-season tires
    An all-season tire is identified by the "M+S" marking on its sidewall. A tire without the "M+S" designation is considered a summer tire.
11. "TEMPORARY USE ONLY"
    A compact spare tire carries the phrase "TEMPORARY USE ONLY" molded into its sidewall. This marking identifies a tire intended strictly for limited emergency use rather than continued everyday driving.
12. Extra load tire (if equipped)
    An extra load tire is constructed to operate at higher load capacities and higher inflation pressures than the corresponding standard tire.

Typical DOT and Tire Identification Number (TIN)

Type A

1. DOT symbol identifying compliance with applicable requirements*
2. Tire Identification Number (TIN)
3. Tire size code
4. Manufacturer's optional tire type code consisting of 3 or 4 letters
5. Tire manufacturer's identification mark
6. Week in which the tire was manufactured
7. Year in which the tire was manufactured

*: The DOT symbol confirms that the tire complies with the applicable Federal Motor Vehicle Safety Standards.

Type B

1. DOT symbol showing applicable federal compliance*
2. Tire Identification Number (TIN)
3. Tire manufacturer's identification mark
4. Manufacturer's code
5. Manufacturing week
6. Manufacturing year

*: The DOT symbol certifies that the tire satisfies the applicable Federal Motor Vehicle Safety Standards.

Tire size

 Typical tire size information

The illustration below shows a typical tire-size designation and explains how the individual numbers and letters describe the tire installed on the Toyota Tacoma.

1. Section width expressed in millimeters
2. Aspect ratio, representing tire height in relation to section width
3. Tire construction code (R = Radial, D = Diagonal)
4. Wheel diameter measured in inches
5. Load index consisting of 2 or 3 digits
6. Speed symbol represented by a single alphabetic character

 Tire dimensions

1. Section width measured across the tire
2. Tire height from the wheel to the outer tread surface
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

The following tire-quality information has been prepared in accordance with regulations established by the National Highway Traffic Safety Administration of the U.S. Department of Transportation.

Its purpose is to provide purchasers and prospective purchasers of Toyota vehicles with standardized information that makes it easier to understand and compare tire quality grades.

If you have questions about how these ratings apply to tires installed on your Toyota Tacoma, your Toyota dealer can provide additional clarification.

 Treadwear

The treadwear grade is a comparative rating based on the rate at which a tire wears when tested under controlled conditions on a standardized government test course.

For example, a tire carrying a treadwear grade of 150 is expected to wear one and one-half (1-1/2) times as well on the government test course as a tire graded 100.

Actual tire life can differ considerably from the standardized rating because real-world performance depends on driving habits, maintenance practices, road surfaces, climate, and other operating conditions encountered during normal use.

 Traction AA, A, B, C

Traction grades range from AA, the highest rating, through A and B to C, the lowest. These grades indicate a tire's ability to stop on wet pavement when tested under controlled conditions on specified government asphalt and concrete test surfaces.

A tire carrying a C traction grade may provide comparatively lower wet-braking performance than tires with higher traction grades.

Warning: The assigned traction grade is based specifically on straight-line braking traction tests. It does not evaluate the tire's ability to maintain traction while cornering or turning.

 Temperature A, B, C

Temperature grades are A, the highest, followed by B and C. These ratings indicate a tire's resistance to heat generation and its ability to dissipate heat when tested under controlled conditions on a specified indoor laboratory test wheel.

Continued operation at high tire temperatures can cause the tire materials to deteriorate, shortening tire life. Excessive heat can also increase the possibility of sudden tire failure.

Grade C represents a level of performance that all passenger-car tires must satisfy under Federal Motor Vehicle Safety Standard No. 109.

Grades B and A indicate progressively higher levels of heat-resistance performance on the laboratory test wheel than the minimum standard required by law.

Warning: A tire's temperature grade assumes that the tire is correctly inflated and is not carrying a load beyond its specified capacity.

Excessive vehicle speed, insufficient tire inflation, excessive loading, or a combination of these conditions can increase heat buildup inside a tire and may ultimately lead to tire failure.

Glossary of tire terminology

*: Table 1 - Occupant loading and distribution for normal vehicle load according to the various designated seating capacities.