Need to know if I have an ABS problem

It's not an ABS problem. ABS prevents wheel lock up on braking, the wheels have to be rotating (at speed) for the wheel speed sensors to count wheel rotation rpm and release and apply brake pressure. This would not apply pressure when you are stopped at a traffic light or cause grabbing. I would remove all wheels and inspect lining material for contamination.

I was curious if you ever found the problem. My 2001 Dodge Ram is doing exactly what you have described but nobody can give me an answer about the cause?