What Causes Trailer Tires to Cup

Question:

What causes a chop or wege shaped wear about every 1.5 or 2 inches in both trailer the choped rubber is only about 1.5 by 1 inch

asked by: Jim

Expert Reply:

What you describe is called 'cupping', where the tire looks like something's been taking bites out of it. Usually cupping on a tire is caused by the tire bouncing on the road, which can have many causes.

Check the air pressure in your trailer tires. A trailer tire should be kept inflated to the maximum air pressure listed on the tire sidewall. Also make sure the weight rating of your tires is not being exceeded.

Having one or more wheel/tires out of balance could also be causing the problem, have a tire shop check your wheels for balance. Trailer tires usually aren't as sensitive to being balanced as passenger vehicle tires, but if one wheel is far enough out of balance it will cause problems.

Closely examine your trailer suspension. As components wear, the suspension can get loose and cause wheel hop. Take a look at your leaf springs and shackle straps, replace shackle straps that have bolt holes that have been worn to the point where they are oblong, instead of round.

Do you pull the trailer while it's empty frequently? Believe it or not, lighter trailers can hop badly when they're empty. Try leaving a minimal load on the trailer.

One or more of these items might be causing the uneven tire wear you describe. I have linked you more information about trailer tires that you might find helpful.

expert reply by: Mike L