Tires with different wear levels on same car?

So, my FWD car has 3 tires that are getting close to replacement tread depth, and one that is only about half worn–it had to be replaced partway thru due to unrepairable damage. The question is whether this amount of difference in tread–maybe 1/8 inch–matters. I could buy 3 and save money or buy 4 and put one away for a good reserve tire. (The spare is different).

Use it for the spare, better to have 4 new matching tires, rotate them regularly.

If you can afford to buy four, do so. Handling and braking will be better especially in an emergency situation…where its most critical.

Consider that you’re only throwing away half the value of one tire, and consider it an inexpensive isurance investment.

Never buy 3 tires…

Look for a 4 for 3 sale at your local tire dealer. Even excellent tires are available this way. Start looking now in case there are good deals available. This gives you time to find a 4-for-3 deal in the next couple of months.

Yep, I’d buy 4 tires and keep the good one in case you hit a curb someday and need another tire.

If this were me, I’d get four, in order to have more balanced handling.

If my advanced math is correct, 1/8 is 4 /32 inch. It is recomended by Tire Rack and others that differences greater then 2/32 inch start creating unsafe handling differences. So “only 1/8 inch” is significant in " tire land". Change them all as everyone says.

Here’s another vote for buying 4 new tires. It will be much safer.