AlexusAnja

I thought that the tire size itself (i.e. 225/70x17) determined the diameter of the tire and that even if you mixed and match tires, they would all be the same diameter.

I recently bought one tire to replace one that had gotten a flat. I did not realize that the speed rating was different. Installed and then the car started to thump. Went to get it looked at and turns out the tires was like over 1" larger in diameter than the other tires and the other tires were not bald either to account for the difference. The technician said the other tires still had about 75% tread.

Does speed rating factor into the diameter? I would think not.

Neo

iTrader: (3)

Speed rating should not matter. Did you get the same tire specs? brand?

SChema

iTrader: (2)

Tire sizes will vary from manufacturer to manufacturer depending on where they measure thread width and side wall height. Some tires run narrow and some run wide for the "same" size tires affecting the overall diameter measurement.

AlexusAnja

Yes, the sizes were the same 225/55x17, same brand and make, just different speed rating. One was 97H the other 94V or something, but same tire basically. Just the overall diameter came out wrong. The technician suggest I return to seller and then that it was possibly a manufacturing error using the wrong mold or something. Who knows...

1uzDreamSC

iTrader: (9)

wow never heard of this happening

svagusta

That shouldn't happen. Your original post said 225/70/17 though, which would be a truck/SUV tire. And your more recent post said 225/55/17. Or was that just a for instance?