Hi,

One of the tires needs to be replaced on my X-Type. I have been hearing conflicting opinions related to replacing single tires on an AWD system. Some say I must replace all 4 while others say I'll be okay as long as the tread depth difference isn't too large. Currently my front two tires are at 7/32" (the tires new are 10/32") and the rear right tire is 8/32". The tire I need to replace is the rear left tire. Replacing with a new tire will give me a tread difference of 3/32" front to back and 2/32" from left to right.

Do you think it will be safe to purchase a single new tire? I looked into having the new tire shaved to match but it doesn't appear that there is anyone local that is able to do it.

 

You'll be fine. Don't bother shaving a new tire. If you are really worded about it, buy two of them, but its not like that little of a difference will destroy your car. I ran a staggered setup on mine for a while with 225 40 18s in the front and 255 35 18s in the back and it was fine, even though the size was a little different. The system isn't THAT fragile.

 

Believe it or not, I've had great success buying accident take off tires on e-bay that are only a year or so old with 80-90% of their tread life left for less than 1/2 of what a new one would cost and then you can get the exact brand and similar amount of wear.

Some of the cars I've got have tires that cost upwards of $300 each and I usually can find nearly new Michelin's for around $100 each on e-bay and now that all tires have date codes on them it's pretty easy to tell how old they are. Personally if they are less than 3 years old and have 75% or more of their tread life remaining I'll take them. This spring I picked up a nice pair for my daughters Jag for $90 that were nearly new.

With all wheel drive, it's best to have the same brand of tire on each wheel so they grip the same in severe weather.

 

It is unlikely that the few mm of tread difference between tyres will make that much odds although purists would likely say otherwise.. If you can afford to I would suggest replacing both tyres on one axle at the same time, but if not it's not a worry..

 

I don't know, given that our transfer cases are supposedly weak, I wouldn't risk the difference. Even though it's just a few mm, it has POTENTIAL to be a bad decision.

An extra couple hundred, at most, to save a $3k transfer case rebuild? Sign me up.

All that being said, I could probably guarantee that nothing would happen but if you can afford it, do both at once and keep the other for an emergency situation or sell it as a single tire replacement for someone that tread depth doesn't mean much to them and you'll recoup some of the cost of that second tire you didn't really want to buy anyways...

Like anything, you get out what you put in. Just my couple pennies...

 

Hi, Arskemp. My very experienced, reliable, reasonable mechanic told me that ideally all four tires should match given the AWD system, etc. I would weigh the following: If your vehicle is in good condition and you plan to keep it for a long time, then go with all four matching. Even if you do what was recommended by purchasing on eBay (or similar). If you are thinking of selling the vehicle in the near future or if the vehicle is experiencing a lot of problems, then going with two or one might be your best bet. I see a lot of X-types on used car lots with mismatched tires. But, that could also be due to stripped lug nuts. Good luck!

 

The differences in air pressure (you'll never get the air pressure balanced to (3/32)/25 = 0.4%) and the fact that the car does not have perfect weight distribution front to rear and side to side will outweigh thread wear effects. If your going to worry about these things you'll have to consider that the sunshine on the tires will change the tire pressures as well. Now there's something to worry about! So under inflate the new tire by 0.6875 psi and you'll be OK.

 

Thanks everyone. Ended up buying new and replacing the single tire.