Note
Tire dimensions
All tires have a designation of dimensions, such as: 265/40 R21 98 W
| 265 | Tire width (mm). |
| 40 | Ratio between tire wall height and tire width (%). |
| R | Radial ply. The designation RF and symbol specify that the vehicle is equipped with puncture-resistant tires. |
| 21 | Rim diameter (inches). |
| 98 | Codes for the maximum permitted tire load, Load Index. |
| W | Speed rating for maximum permitted speed, Speed Symbol. |
Wheel rim dimensions
All wheel rims have a designation of dimensions, such as: 8J x 19 x 50
| 8 | Rim width (inches). |
| J | Rim flange profile. |
| 19 | Rim diameter (inches). |
| 50 | Offset in mm (distance from wheel center to wheel contact surface against the hub). |
Weather condition classification
Here are some classification examples. Weather capabilities can also be defined with certain symbols.
| M+S or M/S | Mud and Snow. |
| AT | All Terrain. |
| AS | All Season. |
Tire age
| DOT YLX2 0819 | Tire Identification Number or TIN. This information helps the tire manufacturer identify tires in the event of safety recalls. |
- DOT1
- The first two characters are the code for the plant where the tire was manufactured.
- The next two characters are the tire's size code.
- The last four digits specify the week and year the tire was manufactured. For example, 0819 means that the tire was manufactured during week 08, year 2019.
Any numbers or letters shown in between are market codes chosen by the manufacturer.
Max load and pressure
| Max load 685 kg (1610 lbs) | Specifies the maximum load that the tire can carry. |
| Max pressure 240 kPa (35 psi) | The maximum tire pressure that the tire should ever be subjected to. This limit is specified by the tire manufacturer. |
Minimum permitted load index and speed rating
The tire load index and speed rating might not be shown on the sidewall as this is not a legal requirement.
Type, materials and tire rotation
| P | Indicates that the tire is for passenger vehicles. |
| VOL | Volvo original tires. |
| Plies: Tread 2 polyester, 2 steel, 1 polyamide. Sidewall 2 polyester. | States the number of cord layers or number of layers with rubber-coated fabric in the tire's tread and sidewall. The tire manufacturers must also state the layer materials used in the tire and sidewall, which may be steel, nylon, polyester and certain other materials. |
| Arrow symbol | Tires with a tread pattern designed to only turn in one direction have the direction of rotation marked with an arrow. |
Classification of uniform tire quality
| Tread wear grade 200 | The tread wear grade is a comparative rating based on the wear rate of the tire in a standardized test. A higher value is better. |
| Traction grade AA | The traction grade is based on standardized straight-ahead braking traction tests. The traction grades, from highest to lowest, are AA, A, B and C. |
| Temperature grade A | The temperature grade reflects the thermal performance of a tire that is properly inflated and not overloaded. The temperature grades, from highest to lowest, are A, B and C. |
From the Consumer Guide to Uniform Tire Quality Grading
The purpose of this section is to aid the consumer in making an informed choice in the purchase of passenger vehicle tires.
All passenger vehicle tires must meet federal safety requirements apart from this classification.
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 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. 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.
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 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 that all passenger vehicle tires must meet under the Federal Motor 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 grade for this tire is established for a tire that 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.
