Tires: tires, tire diameter, gmc envoy

Question
Do you need to have the same model of tires on all four wheels on a 4 wheel suv? I have a 2003 gmc envoy sle and I blew one of the tires so I need to buy a new one but the originals are a lot of money. Can I buy a cheaper tire?

Answer
Shawn,

This is really about how tolerant a particular vehicle is to differences in tire diameter - which is a question that should be asked of the folks that designed the vehicle.

But the rule of thumb is that AWD's and 4X4's have to have 4 of the same tire with the same amount of wear to keep the differences in tire diameter within a level that will prevent damage to the drivetrain.  To do otherwise is to risk an expensive drivetrain failure - and the size of the risk is dependent on how tolerant a particular vehicle is to these differences.  Some vehicles are particularly sensitive - and some are not.