What Do the Numbers and Letters on Car Tires Mean?
2 Answers
Car tire numbers and letters indicate: 1. The first number represents the tire's section width, which is the width of the contact surface between the tire and the road during normal driving; 2. The second number represents the aspect ratio, and 'R' indicates that the tire is a radial tire with steel belts; 3. The following number indicates the rim diameter. The functions of tires are: 1. To transmit driving force, braking force, and steering force for vehicle operation; 2. To support the vehicle's load; 3. To reduce and absorb vibrations and impacts during driving, preventing severe vibrations from damaging car components. Tire maintenance methods include: 1. Regularly removing stones stuck in tire treads; 2. Minimizing exposure to direct sunlight; 3. Promptly checking tire pressure; 4. Paying attention to suspension maintenance; 5. Regularly inspecting front wheel alignment; 6. Being mindful of driving habits.
Those numbers and letters printed on the side of car tires, like the common sequence such as 215/65R15 95H, are something I often help car owners interpret as someone who has been repairing cars for many years. 215 is the tire width in millimeters, indicating the width of the contact patch; 65 is the aspect ratio, which is the percentage of the tire's height relative to its width—65% means the sidewall is quite tall; R stands for radial construction, which is now the mainstream; 15 is the rim diameter in inches, and it must match the corresponding wheel size; 95 is the load index, corresponding to the maximum weight the tire can bear—95 equals approximately 690 kilograms; H is the speed rating, allowing a maximum speed of 210 km/h. These details aren't just for decoration—when replacing tires, they must match accurately, or they could damage the suspension or affect handling. Some high-end cars also come with a ZR code, indicating high-performance tires, which those into car modifications should pay attention to. In short, understanding these can prevent safety issues, and I always advise car owners to check their manuals to confirm the parameters when servicing their cars.
