Tires
Good to go
6–14 mmFull tread depth, tire is performing as designed.
Replace soon
3–5 mmTread is wearing down, plan to replace in the next few months.
Immediate change required
1.6–2 mmAt or below legal minimum, replace immediately.
Check at least 3 different spots across each tire — uneven wear means alignment or suspension issues, not just normal wear.
Tread wear indicator bars are small raised bars built into the tread grooves of every tire. When the tread is flush with these bars, replace immediately.
Quarter Test

Good to goReplace soonReplace now
Insert a quarter into the tread groove. The more of Washington's head you can see, the sooner the tire needs replacing.