Alignment and tire rotation

[bob_ninja]

I have a Mazda Protege which didn't have a tire rotation for a long time as far as I know. They still have about 3-4 mm tread. I think the rule is when only 1mm tread is left then replace, so these should still be Ok. Also we hit a few bumps here and there, so I took it for alignment. The service man told me I also need a new set or tires, which I declined. They are not new, but 3-4mm tread should still be fine.

After alignment my wife told me it still drifts to the left, albeit less than before. She went back to ask why and after a test drive he told her that tires are [censored] and causing the drift.

My questions are about rotation and tread. When do tires need to be replaced? 1mm tread? 2mm tread?

When rotating I didn't pay any attention to tread. I just tried to do the usual back/front swap. Should I also try to match the tread depth? Am I supposed to measure tread on all tires and place the worst pair in the back and the best pair in the front regardless of their previous position? In general what are the main factors when choosing the new placement?

Can different tread depth cause car to drift to the left/right even after a perfect alignment?

thanks

 

[XS650]

1mm is about where the wear bars are even with the tread. 2mm is a better time to replace than 1 mm. 1mm is pushing it.

You shouldn't let one end of the car get much more worn than the other, put the least worn tires on the fastest wearing end when you rotate to even out wear.

 

[bob_ninja]

So you suggest taking off all tires, checking each individually for wear and simply placing best 2 front (most wear at front).
That must have been my mistake.

 

[Quattro Pete]

Originally Posted By: bob_ninja
They still have about 3-4 mm tread. I think the rule is when only 1mm tread is left then replace, so these should still be Ok.

OK for what? You need to be more specific. For dry traction, even no tread will be fine, but not for rain or snow. Do you use these tires in the winter? If so, most tires become pretty useless in snow by the time they're half worn. Here is some more info about tread depth and performance...

http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=51
http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=157

Quote:

and place the worst pair in the back and the best pair in the front

This is a common misconception. Better tires should be mounted in the back. That's because for an average driver it is easier to control a situation where the front of the car loses grip. The more dangerous situation is when the rear loses grip and the car starts spinning around. By having better tires in the back, you minimize the risk of the rear spinning around. Here's more info on this subject:

http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=52

 

[XS650]

Originally Posted By: bob_ninja
So you suggest taking off all tires, checking each individually for wear and simply placing best 2 front (most wear at front).


No need to take them off to check wear.

Yes, If you want them to wear our at about the same time the tires with the most tread should be rotated into the positions with the most wear.

 

[XS650]

Originally Posted By: Quattro Pete
Better tires should be mounted in the back. That's because for an average driver it is easier to control a situation where the front of the car loses grip. The more dangerous situation is when the rear loses grip and the car starts spinning around. By having better tires in the back, you minimize the risk of the rear spinning around. Here's more info on this subject:




You need to use a little common sense along with that. If one blindly followed that advice on a front wheel drive car, they would completely wear out the fronts and have rear tires with most of their tread remaining.

It's best to keep wear roughly even.

 

[Quattro Pete]

Originally Posted By: XS650
You need to use a little common sense along with that. If one blindly followed that advice on a front wheel drive car, they would completely wear out the fronts and have rear tires with most of their tread remaining.

What's wrong with that? Then you move those rear tires to the front and buy 2 new tires for the rear.

I agree that keeping all tires at approx. the same tread depth is best, though.

 

[alreadygone]

"Can different tread depth cause car to drift to the left/right even after a perfect alignment?"

Possible , but not likely. Much more likely is wear pattern or tire separation is causing pull. Simplest way to tell if it's tires or alignment not quite right is to swap sides with front tires, then test drive. If pull is different or gone it's bad tires. If pull is the same, alignment's not quite right.

Bob

 

[bob_ninja]

Originally Posted By: Quattro Pete
Originally Posted By: bob_ninja
They still have about 3-4 mm tread. I think the rule is when only 1mm tread is left then replace, so these should still be Ok.

OK for what? You need to be more specific. For dry traction, even no tread will be fine, but not for rain or snow. Do you use these tires in the winter? If so, most tires become pretty useless in snow by the time they're half worn. Here is some more info about tread depth and performance...
....


Ooops, sry, should have mentioned ....

My Honda CRV is the primary vehicle for winter driving. The tires are on Mazda Protege which is mostly used in summer or on dry roads during winter. So road conditions are always good. That is why I am not too concerned with less tread, within reason of course.

The tires are some sort of sports tires. The previous owner seemed to think he is a Formula1 driver

Anyway rotation was neglected for some time resulting in uneven wear. I rotated them this autumn so better tires are in the front. I probably should replace the weak pair, except I'd like to change the entire set to something more reasonable, all weather all purpose type.

 

[bob_ninja]

Originally Posted By: Quattro Pete
....

This is a common misconception. Better tires should be mounted in the back. That's because for an average driver it is easier to control a situation where the front of the car loses grip. The more dangerous situation is when the rear loses grip and the car starts spinning around. By having better tires in the back, you minimize the risk of the rear spinning around. Here's more info on this subject:

http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=52



I read the article and understand its point. Still I will not follow its advice because the specified condition "oversteering" is very rare and never happens when the speed is properly adjusted to the road condition. I only did it once on a icy road because I was going far too fast, I was upset or something. Here in Canada we learn very quickly (easy or hard way

to adjust speed to rain, ice and snow, so for me at least hydroplaning doesn't happen.

Last winter in early spring there was a flash freeze on roads. Even my CRV with Michelin X-Ice tires and 4 wheel drive started sliding as soon as I tried to accelerate above 30 mpg!!! And this was on a 50 mpg limit road, straight not curves or anything tricky.

Anyway, my approach is to maintain tires and control my speed. I cannot remember the last time I was hydroplaning. Still interesting info. thanks

 

[bob_ninja]

Originally Posted By: alreadygone
"Can different tread depth cause car to drift to the left/right even after a perfect alignment?"

Possible , but not likely. Much more likely is wear pattern or tire separation is causing pull. Simplest way to tell if it's tires or alignment not quite right is to swap sides with front tires, then test drive. If pull is different or gone it's bad tires. If pull is the same, alignment's not quite right.

Bob


The tires which used to be at the front and now are in the back are ready for replacement. I'll change them in the summer.

Difference between the 2 in the front is only 1 mm. They are still in a reasonable shape, not great. I measured again tonight.
I also checked the pressure with a digital device and they are close, less than 1 psi diff.

I'll try that. I'll drive it myself this weekend and see the extent of drift, direction, etc. Then I'll swap the front tires and see if there is any difference.

At this point I am thinking that uneven wear (not doing rotation) combined with one pair being worn out is the main reason. The service guy told me they are [censored] and should be replaced, except he assumed it is my primary winter vehicle. The front tires still have 3-4 mm, which is sufficient for now, until the summer when it is much more convenient to buy new ones.

I am not the original owner, so I don't like the current set, some racing brand. Therefore I'd like to change the entire set, not just the weak pair. Of course I cannot mix a pair of racing with a pair of all season tires.

BTW, any recommendation for all season tires, like I said mostly for good road conditions type driving, Mazda Protege???

thanks

 

[Dyoel182]

As a fellow Mazda driver I can suggest the Falken 512 or 329 as a good all season tire. The 512 actually used to be classed as a summer tire so its a little grippier than the average all season.