Truck Tire Inspection & Blowouts

A steer tire blowout at highway speed can pull a truck off the road or into oncoming traffic. Most blowouts start with underinflation, overloading or damage that a careful inspection would catch. Tires are also among the most common roadside inspection violations.

• Truck drivers
• Bus drivers

Inspecting tires

• Pressure checked with a gauge, not by thumping. Thumping can’t tell 70 psi from 100 psi
• Steer tires have at least 4/32 inch of tread; other tires at least 2/32 inch
• No cuts exposing cords, bulges, bubbles or separations
• No objects stuck between dual tires
• Duals not touching each other and matched in size
• Valve stems and caps in place
• Wheels: no cracks, missing or loose lug nuts, or rust streaks from lug nuts
• Hubs not leaking oil

Why underinflation is dangerous

An underinflated tire flexes more, builds up heat, and can come apart at highway speed. One flat tire in a set of duals overloads its partner. Check pressures when tires are cold, at the start of the day.

If a tire blows out

1. Hold the steering wheel firmly with both hands.
2. Stay off the brake at first; braking can pull the truck toward the blown tire.
3. Let the truck slow down. Keep it in your lane. If the tire is a steer tire, you may need to accelerate slightly to keep control, then ease off.
4. Once you’ve slowed and have control, brake gently and pull completely off the road.

Warning devices

When you stop on the shoulder, turn on your flashers and put out your three warning triangles within 10 minutes:

• Two-lane road: one about 10 feet behind the truck, one about 100 feet behind, and one about 100 feet ahead.
• Divided highway or one-way road: about 10, 100 and 200 feet behind the truck.
• Hills and curves: place one farther back (up to 500 feet) so drivers get warning before they see the truck.

Wear hi-vis, walk facing traffic, and stay off the travel lane.

Changing truck tires

• Truck tire and wheel service is dangerous: multi-piece and split rims can explode with deadly force when inflated. Only trained workers using a restraining cage and a clip-on chuck with a remote valve should do it. See Diesel Mechanics.
• On the roadside, call a tire service. Don’t try to change a truck tire next to traffic.

Last updated: October 1, 2026