rear disc brakes on 8 3/4

Buschi340 said

72bluNblu ,
very good Point. Didn't know about that off set. but can't be that much. It is working this way since 3 years. But you are right. I saw that the linings are not centered in the drums. One reason more to Change it to discs. :)
ok, got yukon BBP axles and green bearings already.

Click to expand...

Well, Yukon is one of the aftermarket suppliers that makes BBP axles with a SBP flange offset. So, it's possible that your BBP axles have a SBP flange offset, which means you would need a disk kit intended for SBP axles but drilled with the big bolt pattern.

The offset isn't much, pretty much just the thickness of the axle flange, but it's more than enough to cause problems. For example, if you use stock BBP drums on a redrilled SBP axle, the drums hit the backing plates and cause interference. That's a no go. If you use redrilled SBP brakes on BBP axles, the drums don't cover the brake linings completely, rendering them significantly less effective than stock. If your brake wear pattern goes all the way out past the edge of your drums, that's probably what you did. Your brake shoes would have a "lip" on them near the backing plate as well.

In either case, you'll need to know which flange offset you have before you buy a disk kit. If your kit isn't intended for the axle flange offset you have, the rotors won't line up with the calipers.