What do the parameters on a tire represent?
3 Answers
The parameters on a tire represent: production date, tire specifications. Taking the 185/60r17 89h tire model as an example, the tire parameters respectively represent: 1. 185 indicates the tire width is 185mm; 2. 60 indicates the aspect ratio of the tire's cross-section is 60%; 3. r indicates the tire has a radial structure; 4. 17 indicates the rim diameter is 17 inches; 5. 89 indicates the load index; 6. h indicates the speed rating. Car tires are one of the important components of a vehicle, directly contacting the road surface and working together with the car suspension to mitigate the impact during driving, ensuring good ride comfort and smooth driving, maintaining excellent adhesion between the wheels and the road surface, improving the vehicle's traction, braking, and off-road capability, and bearing the weight of the car.
That string of numbers and letters on the tire can be confusing, right? Take something like 235/55 R18 101V—let's break it down: 235 is the tire's cross-sectional width in millimeters; a larger width generally means better grip but also higher fuel consumption. 55 is the aspect ratio, indicating that the tire's height is 55% of its width. A smaller number means thinner sidewalls, which improves sportiness but reduces comfort. The R stands for radial construction, which over 90% of tires use today. 18 corresponds to the wheel diameter of 18 inches; when changing wheels, this number must match. Finally, 101 is the load index, which, when checked against a table, shows a maximum load capacity of 825 kg. The V is the speed rating, indicating a maximum speed of 240 km/h. Sports cars often use W or Y ratings.
When changing tires, don't just focus on size matching—those small characters at the back are more important! Last time I helped my neighbor check his tires, they were marked 98H. The 98 means each tire can bear 750 kg, so four tires together can support 3 tons. The H indicates a maximum speed of 210 km/h, which is sufficient for regular family cars but performance vehicles need special attention. The production date is also hidden on the side, something like 3223 means the tire was produced in the 32nd week of 2023. Tires age in just three years, so even if the tread is deep, they should be replaced. Recently, I've noticed many new tires come with an MOE marking, which indicates they are Mercedes-Benz certified specialty tires.
