How do I know if my tires need replacing?

Concerns & risks

You were trying to decide whether your car is safe for a winter road trip, but the tires are a few years old and you're not sure how worn is too worn.

Bald tires lose grip, especially on wet roads.

Causes & evidence

Tires should be replaced at 2/32 inch of tread. Use the penny test and look for cuts, cracks or bulges. See tire pressure and tread.

What to do

1. Put a penny in the tread, Lincoln's head upside down and facing you.
2. If you see the top of his head, replace the tires.
3. Check the treadwear indicator bars between the grooves.
4. Look for bulges or cracks on the sidewalls.

Common mistakes: Common mistakes: checking only one spot. Tires often wear unevenly, more on the inside or outside edge, so check several places across each tire. Uneven wear can also signal alignment or pressure problems worth fixing so the new tires last. Another mistake is replacing just one tire on some all-wheel-drive cars; check your manual, since mismatched tread can matter. When buying, match the size and load rating shown on your door placard. Keep the receipt and note the date so you can track tire age.

Speed Man tip: Check several spots on each tire; wear can be uneven.

Wrap-up: Penny test. 2/32 inch = replace. Bulges are a red flag.