I installed new shoes on the rear of a 96 dodge ram 4 months ago. I also replaced both rear wheel cylinders and flushed what looked like the original fluid. The truck ran fine for the last four months. Now:

If the truck has been sitting, and you go to move it, the first two times or so you apply the brakes both rear wheels will lock up a bit. After that they opperate normally? I'm perplexed!!!