My rear tires (Nokian) on my Subaru Legacy 1999 all wheel drive car are noisy and chopped after only 18,000 miles (tires were in front for 4,000 miles; at that point I had to get two new tires which were put in front). My mechanic does not recommend rotation so they haven’t been rotated. No, I don’t know why. So now they are chopped but have lots of tread. What the heck? Any suggestions?
What is the difference in tread ( x/32nds) between the front and rear tires?
“My mechanic does not recommend rotation so they haven’t been rotated”
You need a better mechanic. Timely tire rotation is crucial with AWD.
Also, when changing tires 2 at a time (and that’s a no-no with AWD) the new tires should go in the back.
The shop didn’t measure, but I just measured and they are the virtually the same. I do not however, have a tire depth gauge.
Thanks for your comments. So even if the difference is only 4,000 miles, you would still get four new tires? Expensive. I will not buy all wheel drive again.
[i] So even if the difference is only 4,000 miles, you would still get four new tires?[/i] You need to have them carefully measured. If they meet the specs found in your owner's manual, then they are good to go or rotated.
Yes AWD is picky about tyres.
I talked to the shop again. They say you should put new tires in rear because with Subaru AWD, 70 percent of power or whatever is in the front, back kicks in as needed.
They also said it’s okay to have up to a 3/32 difference in tire size. Not true?
To expand on what the others have said, on a Subaru, the circumference of all tires needs to match within a certain tolerance to prevent damage. This should be stated in your manual. If you don’t rotate the tires, they’ll wear differently, so that they no longer match.
for Subarus, measure circumference around the center of the tire, compare all four. Believe the allowable range is 1/4 " or so. It is in your owner’s manual what the allowable range is and how to measure. Need to do it to see just where you stand.
Second choice is to find a tire shop to take enough tread off all four to bring them into spec.
If the tire pairs are different make/model then you need to remeasure or risk ruining the AWD.
Nokians are incredible winter tires and do stay quiet with regular rotation. However I have been warned by two places that irregular rotation leads to excessive noise with them.
Subaru recommends rotation every 7500 miles I believe. I do it every other oil change but occasionally skip.
So, all tires are at 11/32, not much wear. They are all the same tire model I believe. However, the mechanic said at this point he did not recommend rotating because the tires were cupped enough that they would make even more noise in the front, and the cupping would never go away, just get worse. The tires are under warranty yet, so I guess it might make sense to get 2 new tires, and move the front tires to the back (although someone said not to) since there would only be 1/12 difference.
Turns out the shop does normally rotate, and for some reason my car fell through the cracks. They also told me that they did not ALIGN my tires the last two times they put on new tires because it didn’t seem to need it trying to save me money. I assumed they had aligned. So now they propose aligning them finally to see if that prevents further cupping. Any opinions on that? Should they offer to do the service for reduced rate, or is it just bad luck for me? Thanks for any further comments. These tires are good on snow.
New shop/mechanic, yesterday.
4 new tires, same time frame.
If the tires are not directional:
Move the back tires to the front, but swap them L-R to reverse their rotation.
That will wear against the “cupping”.
Move the fronts straight to the back.
For many cars this is the normal rotation pattern.
Just so you know, new tires always go on the back on all cars, no matter what drive system they have. Putting new tires on the front can cause a spin, likely followed by a crash.