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Change All Four Tires?

I have been told that, with an all-wheel drive car (such as an EVO x or Subaru), if I should, by chance, mess up one tire, I should replace all four tires, rather than only the bad one, or else I can do damage to some part of the drive train by running on uneven tires. Is this true?

Yes. Just look in the owner’s manual. All 4 tires have to be exactly the same diameter.

Its that, or you disable the 4WD system on the Subaru by removing the fuse, and just run the car as FWD.

BC.

Yes, the only other option is to have the new tire ‘shaved’ to the identical diameter, but you’ll want to figure this out (find a place that does it) before the problem comes up.

That is true IF that particular Subaru has a provsion for inserting a fuse in order to enable FWD/disable AWD.

If the vehicle in question has the more advanced Variable Torque Distribution (VTD) AWD system, there is no provision for inserting a fuse for this purpose. While the VTD system is much more resistant to damage than the “regular” Subaru AWD system, it is still a very bad idea to drive more than…let’s say…50-100 miles…on mismatched tires.

The disable AWD only applies to majority of automatic Subaru models. However none manual transmission models you can disable it.

Even disabling, it is considered a temporary measure.

Evo I have no idea.