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Tire replacment on all wheel drive car

My wife had a flat tire that needed replacment. The tire shop convinced her that she needed to replace all 4 tires because the Subaru Forester is an all wheel drive car. The tires were less than 25000 miles old. I can see replacing 2 so the left and right match but not all 4. Well, we have another bad tire and I don’t want to feel shafted again so, what is the right answer 2 or all 4?

I understand from your question that the tires you have now are fairly new, so I would just replace the bad tire. If there is something wrong with the tire due to manufacturing, there should be a warranty on it and that same tire shop should replace it.

What’s your manual say? The Subarus are much more sensitive to size mismatches fron to rear.

With most tires, significant wear takes place after 25,000 miles, so I am going to disagree with Wizard that these tires are “fairly new”. If you check with the Subaru dealership (or consult your Owner’s Manual), you can get the official word on how much of a difference in tire circumference is critical on this vehicle.

I would advise you to buy 4 new tires. Buying just two is really not going to cause less damage to the center differential than you would cause by buying just one tire. Bear in mind that if you try to “cheap out” on the tire issue, you could well wind up wearing out the center differential on this vehicle–and that is far more expensive than a set of 4 tires.

Knowing Subarus, as I do, I am going to venture that 25,000 miles of wear is far too much for you to match one or two new tires to those old ones. However, there is a lower cost solution than buying 4 new tires. The more sophisticated tire shops can “shave” a new tire so that its tread depth matches that of the old tires. All in all, this is your most cost-efficient solution, because it would allow you to buy just one tire. The trick is finding a tire shop that can do this for you.

There will be substantial wear after 25k miles and if the difference between the used tires and the new MATCHED ones is more than 3/16" in circumference, then 4 of the same (size/tread and make) are needed to prevent transfer-case damage. (a transfer case is like a center differential).

It because of this problem I refuse to buy an AWD vehicle.

A few things.

Subaru’s rule is

If sell your tire you can mail order it from and have the tire shaved down. There prices are pretty reasonable typically if not better than most shops shipped.

They should have suggested shaving the tyre down to match the existing tyres.  This can save you some money.  The one thing you don't want to do is go driving around with different size (wear) tyres.  That can cost you a lot more than four new tyres.  

That is part of the price you pay for AWD.  Do you really need all wheel drive?  Remember than it does not help you stop faster or keep you from sliding off the side of the road, it only helps you get back on the road after you slide off. :-)

The cost to repair a damaged AWD system on a Subaru, caused by mis-matched tires, is much more than the cost of a set of tires. At 25K miles, your tires are worn more than enough to exceed the 1/4" circumference allowance that Subaru specifies.

This, unfortunately, is one of the hidden costs of owning a Subaru, but the sophistication of the AWD system is worth it, in my opinion.

I too had an '02 Subaru on which one tire was ruined and went to replace with a new one. I was given the same information by the tire dealer I use regularly. I ended up putting my snow tire set back on the car thus saving approx. $500 and then trading in the car. I went on line and googled transfer cases and tires and discovered the problems with most all wheel systems in hundreds of articles and tech bulletins from many manufactures. I have also decided to go with a decent front wheel drive and have good snow tires to move through the winters. Who knew, like many things dealing with cars, the advertising is about the show of a new car with lots sparkle and NO problems or warnings.

I agree that AWD does little to stop a vehicle. However if you are sliding and tap the accelerator it can help you claw your way back onto the road with available traction significantly better than any FWD vehicle.

I have over 20 years experience with AWD vehicles(AMC/Audi/Subaru) the whole time a few FWD’s. How much do you have?

The way I read their post, they had a bad tire, bought 4 new tires and now have ANOTHER bad tire. If that is the case, then just the one tire should be enough, unless you’ve put an ornate number of miles on them since you got the 4 new ones.