Rear pup trailer trailer axle ruining tires one side only

The rear drivers side on the most rear axle of my pup setup is destroying the tires.... I backed the brakes off and the problem stopped for a bit, but when the next driver adjusted them properly and drove on dirt roads it ripped 3inch long by 1 inch wide by 1/2 inch deep chunks out of the tread. And it did that in about two days or less.... It's not all over the tire in any uniform manner it appears to always be in just one spot .

When I first got into the rig, it looked as though someone had drug these tires with a frozen brake for a bit.... Whole tire is fine.... But that one spot. Across both tires on that side.

We haul crude oil so that pup is always liquid filled or empty.

But I wanted to see what you guys thought it could be....

If it was anything like a kinked hose etc, or something causing the brakes to set when we hit a bump in the road, the. The wear would be all over the tire in random spots.... So I'm kinda stumped.

This is an older unit.... 1991 and other than new brakes and maintenence I don't think anything else has been done to it.


Any ideas and how I would test these theories to find out before we ruin another 1000 dollar set of tires but thinking we've got it fixed only to be proven tragically incorrect. ; ).

This is our third set.

 

Hmmmmm...... I'm can't be sure, but it's had three sets of tires put on it, so if I'm understanding, your hypotheses is based on the tire guys not tightening those up properly?

Is is that right?

And could I raise the axle up on that side and spin the wheel with the brakes properly adjusted to determine if there is a spot that catches badly...?

 

Unfortunately both sets of tires were trashed by the tire guys.... So no pics, but literally all damage is confined to an eight inch section on the tire.

 

Any other ideas or ways to test them?