I rebuilt the rear calipers that came with my disk brake diff, I used all the correct lubes and rebuild kits, but they are really really stiff. Had to grip the piston in a vice to remove it by working the caliper from side to side. The bores had plenty of fluid in them to aid movement, but I'm sure the pistons are not supposed to be this tight. The hand book says you should be able to get the piston out of the bore by simply using an air compressor. Yeah right. Should you be able to move the piston using only your hands? When I tried bleeding the system, the rear brakes simply refused to budge. Any idea what is wrong? I've got no problem forking out for some new calipers, but it would be easier to fix the ones I have. Which Commodores use the same rear calipers?

i have a set of calipers here tom if you need some,pm me? dont really know why they wont move

any of the VN-VR solid rear diff rear calipers will fit, are the pistons rusty?causing them to be physically larger and bind up

Pistons aren't rusty, cos I did wonder if that might be the cause. Should you be able to move the piston with your bare hands?

probly not on rebuilt ones as they should be tight id guess, i usually use a clamp to push the piston in etc