With this simple check, when it comes to your tires and protection, a penny will buy you peace of mind:
Place a penny head over the tire first through several tread grooves.
Your treads are shallow and worn if you still see the very top of the head of Lincoln.
If this is the case, there is a need to change your tires.
If you see his forehead then you can wait on new tires.
You have more than 2/32 of an inch of tread if part of Lincoln's head is still hidden by the tread.