Penny. You can use a penny to test tread wear on your tires. To test the tread, you insert the penny in the grooves on your tires head down. It is as if Lincoln is diving heardfirst into the tire. If you can see any part of the word 'WE' your tires need to be replaced. It's important to notice if the tires are wearing unevenly so it's important to check tread on the inside, middle and outside. If any part of the tire is wearing unevenly, you may have a problem with misalignment or balance.
