Quote Originally Posted by Wobert View Post
No, the speed rating of the tyre has to be in line with the max speed of the car. A 136 TDie has a vmax of 130 mph so the tyre speed rating has to exceed this. In this case you could use a V-rated tyre as at 150 mph this also exceeds thevamx of the vehicle.

In a lot of cases the tyre manufacturers limit the number of speed ratings thay make for a given tyre type and size, so usually go with ratings that are towards the top end of those vheicles they will be used on.

As others have pointed out, the load index is a much more critical number to match correctly.
Thanks for the reply and clarification.

I have always been led to believe, certainly by most tyre dealers, that you have to maintain the original manufactures fitted speed rating.

So why on earth do manufactures fit tyres that are some two or more speed ratings above the actual max speed of the car?

Are the characteristics of the lower rated tyres, grip, noise, wear etc significantly worse than those of the higher rated tyres to justify the extra cost they very often demand?