is it safe to have a different diameter tire on the back wheels than on the front
i have a ford flex and I've acquired a set of tires for the rear
but they are a smaller outside diameter than the set that is on
Not really it can throw off the ABS and if it is an AWD it can ruin the transfer case, it will also handle differently at higher speeds and may cause some instability during a cross wind situation. Tires should all be the same size and to be safe the same manufacture.
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