Tire speed rating V
For example, if the tire has a speed rating of V, then the maximum speed it can sustain is 149 mph (240 km/h).
Can I switch to a tire with a higher speed index?
When your tires are worn out, it is perfectly possible to replace them with tires with a higher speed index than the one indicated on the old ones. However, you should never mount tires with a lower speed index unless fitting tires with winter capacities such as winter tires or All Season Tires, as discussed below.
Choosing a lower speed index for winter tires
If you use tires with winter capacities (marked 3PMSF : either winter tires either All Season tires), the speed rating may be lower than that of your summer tires or the original tire fitted to your vehicle. Why is this possible? tires with winter capacities are designed differently for driving in difficult climatic conditions (snowy, icy roads, etc.) and may not have the same speed rating. However, generally you drive at a lower speed in winter than you would on dry roads with summer tires. In any case, the driver must limit the speed of the car so not to exceed the maximum speed of the tire.
