On my 98 F150 4x4 the driver side inside pad is dragging and wearing really fast. Does anyone know if that is a slider lube issue or a caliper piston retraction issue?

 

Since the pistons are inboard and that's the side that's wearing more than the other, it sounds like binding pistons, but it could be either. Since you have to do one or the other, might just as well strip it and rebuild it or trade it in on an already rebuilt unit.

 

I assume a rebuild would also require a blead since the caliper has to come apart. ?

 

Ya, you'll have to bleed it.
If you have a buddy help, no problem.
If not, just let it gravity bleed.