Did you replace the shoes? Mine were "new" when I bought my truck, but the beast had been in the barn and the shoes were saturated with grease. As I said, they looked great...but would not stop my truck. The shoes would not release after locking up the wheel. I had to back up at stop signs to unlock the brakes.
I also re-adjusted mine several times..
Adjustment and grease requiring new shoes were my problem.
