What do the letters in tire speed ratings represent?

2 Answers
DiPatrick
07/25/25 1:24am
Letters from A to Z represent the certified speed ratings of tires, ranging from 4.8 km/h to 300 km/h. Here are the relevant details: 1. Generally speaking, the further the letter representing the tire speed rating is in the alphabet, the better the tire's performance, and the higher its price. 2. Tires with different speed ratings have different applicable ranges. P—T grade tires (maximum speed 150—190 km/h) are suitable for small and compact cars, U—V grade tires (maximum speed 200—240 km/h) are suitable for mid-to-high-end cars, while the highest-performing W—Z tires, which can withstand speeds between 240—300 km/h, are typically used in large luxury cars and supercars.
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BlakelyRose
08/10/25 4:07pm
I've been driving for over a decade, and the speed rating letters on tires are truly crucial. Common ones like H represent a maximum of 210 km/h, while V stands for 240 km/h. Different letters indicate the safe limits a tire can withstand under high temperatures and speeds. Choosing the wrong one can be dangerous—on highways, tires can soften and overheat if driven too fast, increasing the risk of a blowout. I remember once helping a friend change tires; he opted for cheaper S-rated tires to save money, and it nearly caused an accident when overtaking on the highway. So every time I buy new tires, I first check the vehicle manual or the label on the door to confirm the recommended rating. Never just pick based on price—safety should always come first.
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