Trailer tires wearing on one edge (or both, or the center)

Uneven trailer tire wear is the trailer telling you what the axle, the brakes or the pressure is doing. Edge wear on both sides is under-inflation, center wear is over-inflation, wear on one side is camber or overload, and flat spots are locked wheels, by Dexter’s own tire wear chart. Typical prices: mounting $12 to $25 per tire plus the tire; axle replacement $400 to $1,800 per axle installed. Check the pressure before anything else.

Check this first

1. Check pressure cold with a gauge, against the maximum on the sidewall for the load you carry.
2. Read the pattern. Run a hand across the tread. Which part is worn: both edges, the center, one edge, toe wear, cupped, or flat spots?
3. Check the load. Is the trailer carrying more than its rating? The gross rating is on the VIN label.
4. Look at the axle from behind. Does the wheel lean in or out at the top? Is one side of the trailer lower?
5. Read the date code. The last four digits of the DOT number are the week and year it was made (49 CFR 574.5). An old tire may need replacing regardless.

Dexter’s tire wear chart

Full ranges are on the pricing page.

Why it happens

A trailer axle can bend from an overload or a hard hit, and from then on the tires on that axle wear on one edge. Flat spots come from brakes locking, often on an empty trailer with the controller set for a loaded one. Cupping can come from loose bearings as well as imbalance, which is why Dexter’s chart says to check bearing adjustment.

Why it matters

Dexter warns that once a wear pattern becomes firmly established in a tire, it is difficult to stop even after the cause is corrected. And a bent axle does not straighten itself.

When to call

If the pressure is right and the wear is on one side, toe wear, or cupped, the axle or the bearings need a look. See axle and suspension repair, tires and wheels and hub hot or wheel noise.