I had a flat tire on the way home a few days ago and had to buy a new tire. The other 3 tires still have tread. Do I need to buy another new tire? Or do I need to buy 3 more new tires? Or can I get by with the 1 new tire and the 3 old tires?
How much tread do the others have left?
In your car you can get by with one odd tire, but it does create imbalances in traction and handling characteristics that could manifest themselves in an emergency situation as an accident. As a minimum the tires on both sides of either end should match. If the tread is getting low on the other three, you should replace them all with tires that match your new one.
Tires are one of the most critical items in having the control and traction you need in an emergency situation. They’re the only connection you have between you and the road. If in doubt, change the other three. It’s dirt-cheap insurance.
The other 3 tires have pretty good tread left but are not like new of course. They would probably need to be replaced within a year anyway
I would buy at least two, and mount the new ones on the REAR axle.
If your car is an AWD Subaru you need four new tires.
It’s a Pontiac Grand Prix. It’s in the “tags” section. I’m having a hard time with this new format too.