Uneven tyre sizes and effects on the drive line

[MattWhite Advanced Member Find all posts View Profile Close MattWhite]

HAHA, it is understandable though. Better things to do than fix your own car!

Matt

[AtiqFuzail Lurker Find all posts View Profile Close AtiqFuzail]

Hi, got one tyre sidewall slashed. So I am in the same situation pretty much. When I measured the same type tyres front and back I find that the radius of the front is 4 to 5 mm lesser than the back tyres. This is surely because the weight of the engine etc. This means that in any case the front tyres are running at a higher rounds by upto a centimetre dia difference. Is the drive train, i.e. The diff and gears designed to handle this? Are the front diff and rear diff different in gear ratio? If not then should we not put the new pair in the front? Maybe it is better to always buy tyres in pairs and put the new one in the front!

[krypto Avid PP Poster! Find all posts View Profile Close krypto]

I noticed one of the posts talked about rotating the spare. I used to rotate my spare and then stopped doing it....big mistake.

Recently I punctured a tyre while in a fairly remote area. The spare was a different size and nearly 6 years old. Very nervous drive, not just because of the driveline issues but also the age of the tyre. I had a really bad blow out on a camper a few years ago. Tyre looked like new but was 6 years old, it absolutely disintegrated when it failed and did quite a bit of damage to the camper. When I replaced it I found out that tyres have a service life of about 6 years, you can get lucky and get a lot more out of them but it's a big risk when you look at what is at stake.