Question: how do i know how much tread is left on my tires?
Answer: Place a penny head first into several tread grooves across the tire. If you always see the top of Lincoln's head, your treads are shallow and worn. If this is the case, your tires need to be replaced. If part of Lincoln's head is always covered by the tread, you have more than 2/32 of an inch of tread depth remaining.