Sometimes auto manufacturers work with the tire manufacturers to make tiny adjustments for a specific car. I remember when I had my E39 M5, I bought deeply discounted rear Michelins from Tire Rack that were orginally designed to be the front tires on a Viper. Apparently, the Viper tires had some reinforcement in the shoulder of the tire. I figured since these were going on the rear and were the OEM M5 size it wasn't going to have a negative impact on anything.For the 295/30ZR-20 rear size, Tire Rack carries an unspecified, a "BMW", and a "Mercedes-Benz" version. What is the difference?
The M5 is heavier than an SL, but I would think the speed rating of the tires would be similar since they have similar performance. Do you think the weight difference matters in the tire selection between BMW and MB?As said above auto companies work with tire manufactures with specific details regarding the tires. I have the MB 295/30/20 version tires standard for the SLS AMG on my car and it was the tread width that was different. The actual width of the tire is the same but the tread width is slightly different. If you compare the tires on TireRack with the BMW and Mercedes version in the comparison chart it will show some of the differences. Michelin can't release all differences because of the agreement with the auto company.
When I bought mine it was $27 cheaper than the BMW version of the same tire and about the same as the regular non-brand specific tire. The TireRack sales guy sold me on the MB version because it was in stock at the warehouse closest to me while the regular non-brand one was out of stock everywhere.
Speed rating is the same between the tires I just looked on TireRack's website. They are also rated for the same max weight of 1,819 of pounds per tire the only differences on the comparison chart are tread width and depth. The Mercedes variant has 10/32 while the BMW has 9/32.The M5 is heavier than an SL, but I would think the speed rating of the tires would be similar since they have similar performance. Do you think the weight difference matters in the tire selection between BMW and MB?