It’s the tread that makes the difference between a steer, drive, and trailer tire. The differences are obvious even to the casual observer – the advantages of each tire are in the mind of the user.

Steer tires allow the vehicle to steer and brake using solid ribs that run circumferentially around the tire. Most manufacturers use a de-coupling groove on the outer shoulder of a steer tire to prevent irregular wear such as scalloping. Tread depth tends to be around 18/32 – 19/32 of an inch.

Drive tires have a single purpose; traction, usually incorporating a lug design. Tread depth is between 28/32 and 30/32 of an inch, with some of the “fuel efficient drive tires coming in a little below that.

Trailer tires are often put on trailers to run out their useful lives. There are also tires specifically designed for trailers, usually rib designs, with a shallow tread depth – somewhere around 14-18/32. Trailer tires are susceptible to irregular wear, so starting with a shallow tread allows less opportunity for bad wear patterns to develop.