Question hoping to find an answer. For years, my left rear brake keeps over-adjusting to the point it will destroy shoes. Right side does just fine. I've replaced all the hardware along with new shoes and drums, as the original drums had 280,000+ on them. Still, with all new components the adjustment is about 5 times that of the right side. Any ideas?

 

Don`t know but if it was me, I would remove the little wire cable from both sides and just adjust them manually about every 10,000mls.

 

The only way the adjuster can be holding them that far apart is if the brake shoes are that open to begin with.

Does the truck pull to the left during heavy braking?

Wheel cylinder maybe?

But if you're replaced literally everything, then I'd suggest taking some very precise measurements on the backplate. It could be that a pin has been moved slightly and is causing the excess wear.

That's just a couple of thoughts off the top of my head.

 

Also, carefully check the brake shoe contact pads on the backing plates - they are flat when new, but often the brake shoe will wear a groove into them over time. This could cause the shoes to hang up on one side and could potentially cause your problem.

I've had similar unexplainable drum brake issues on a car I used to own - the rear brake hardware on one side would come out of place, after I had replaced everything with new same as you. I kept gloves and vise-grips in the trunk so I could put the springs back on while out on the road. Never did figure out why that was happening. VERY frustrating!