Super D

I have a pull to the left after a new tire install. Took car to alignment shop, checked alignment, no problems. They say it's a problem with one of the tires, and that it's defective.

Have you ever heard of something like this?

Norm Peterson

Can't say I've ever had the problem myself, but it's entirely possible. There's something called 'conicity' that's involved here.

See CONICITY, about a third of the way down the page.


Norm

Super D

Thanks Norm, checked that out, very interesting.

91 Fox 331

Yeah ive been workin in a shop for three years and that is more of a common problem than you might think. what he said about conicity is the most probable cause. Out of round will be more of a vibration than anything. Take it back to the shop where you bought and it let them know about your problem, most shops will exchange the tire and send it back for warrenty. you could also have them rotate it to the other side and if it pulls to the right, the tire is your problem for sure.

socalwrench

Generally, a pull is caused by a suspension problem. This can cause a tire to wear abnormally, and make the pull worse.

However, if the tire is defective, I suppose it could. The tire would have to be severely messed up in my opinion- I don't think it would balance very well.

Norm Peterson

Maybe it wouldn't balance very well, maybe it actually would. It's not necessarily the sort of nonuniformity that must be associated with imbalance.

Belt ply cords are not purely circumferential, and I think if subsequent belt(s) are slightly offset laterally (i.e. across the tread) you end up with a net lateral force at the contact patch even though the static and dynamic balances could both be very good. I suspect that all tires exhibit this to at least some minute degree, and as long as you don't get a tire that slips past quality control limits you'd never realize it from seat-of-the-pants or feel it even if you knew about the existence of this phenomenon.


Norm