Trailer Tire with Flat Spots and Bulge on the Tread on a Harbor Freight Trailer with 4.80-12 Tires

Updated 03/22/2016 | Published 03/21/2016

Question:

After a recent 760 mile trip I was shocked after waking up and looking at the trailer in daylight. The right-hand side tire had excessive wear on just one spot. Trailer in question is a HarborFreight folding trailer with 4.80/12 tires. Wheel when jacked up was spinning without problem and noise. It was getting a bit late and on the last stretch I drove a bit faster than the speed rating of the tire 55mph, I have reached 70mph a few times. Could this have caused this wear? Rubber on the spot was very thin and was almost able to push my finger through. Have to admit they were still the original wheels the trailer came with with less than 2500 miles on them. Am looking to upgrade to the AM3S030 but still have to convince the wife and measure to see if I have enough clearance. Will this tire have a higher speed rating? Am regurlarly doing the 760 mile trip and with stops and 55mph it takes pretty long.

asked by: John

Expert Reply:

It looks like the tire has flat spots or some cupping going on. flat spots usually occur from locking up tires (with brakes) causing the tires to skid. Cupping comes from tires that are not balanced and possible bearing problems.

That bulge appears to be symptomatic of the belts or plies inside the tire in that location failing which could have been caused from excessive heat which may have been a result of going over the speed rating of the tires.

You can replace the 4.80-12 tires that you have with # TTWSF48012C rated for 81 miles per hour. That way you can get where you are going sooner! Please note that trailer tires should be inflated to the maximum psi indicated on the tire to avoid failure from excessive heat.

expert reply by: Michael H