A simple step-by-step guide for Upland, CA drivers — no mechanic required.
Proper tire maintenance is one of the easiest things you can do to stay safe on the road and save money at the pump. Whether you're commuting through Upland or heading out on the 210, healthy tires make all the difference.
Here is a simple guide to checking your tire pressure and tread depth at home — no mechanic required, and it only takes about five minutes.
Digital or stick-type, available at any auto parts store for under $15. A digital gauge gives the easiest reading, but a simple stick gauge works great too.
That's right — a simple penny is all you need for the classic tread depth test. Grab one from your glovebox or cup holder.
Check when cold. For an accurate reading, check your tires before driving or at least 3 hours after your last trip. Heat from driving increases pressure and gives a false reading.
Find the correct PSI. Look at the sticker on your driver's side door jamb — not the tire sidewall. The sidewall shows the maximum pressure, while the door jamb sticker shows the manufacturer's recommended PSI for your specific vehicle.
Measure and adjust. Remove the valve cap, press the gauge firmly onto the valve stem, and read the pressure. Add air if it's low, or release air by pressing the pin inside the valve stem if it's too high. Don't forget to check all four tires plus the spare!
Pro Tip: Tire pressure drops about 1 PSI for every 10°F drop in temperature. Check your tires more frequently during seasonal changes here in Southern California.
Take a penny and insert it into the tread groove with Lincoln's head facing down into the tread.
If you can see all of Lincoln's head, your tread depth is below 2/32 of an inch — the tire is worn out and needs replacement. If part of his head is covered by the tread, you still have adequate tread depth.
Important: Check tread depth in multiple spots across each tire — inside, center, and outside edges. Uneven wear could indicate alignment or inflation issues.
Tread is below 2/32" — replace the tire
Tread is adequate — your tires are safe
If the inner or outer edges are more worn than the center, you may have alignment or inflation issues that need attention.
Visible cracks, cuts, or bulges in the sidewall are serious — these tires can fail suddenly and should be replaced immediately.
Persistent vibrations, especially at highway speeds, can signal an out-of-balance tire or internal tire damage.
If you're constantly adding air to the same tire, there's likely a slow leak from a puncture, valve stem issue, or bead seal problem.
Our ASE-certified technicians at 123 Auto Center can inspect your tires, check alignment, and make sure you're safe on the road.
2133 W Foothill Blvd, Unit A
Upland, CA 91786
Monday – Friday
8:00 AM – 5:00 PM
Call us at
(909) 527-2525
No appointment needed — walk-ins welcome!