8.75 Rear End Drum Brakes
Sounds like you have a mismatch between your axles and your brakes. SBP axles have a different flange offset than BBP axles-
And what that means is that the backing plates also have different offsets. So, the backing plate for a 10x1.75" SBP drum brake set up can not be used with BBP axles, you have to use a backing plate for a 10x2.5" drum set up. No mixing and matching of axles and backing plates.
To measure the backing plate offset you want to set the backing plate flat on a bench. You'll need to hang the bottom 1/3 of the backing plate off the edge of the bench so that the mounts for the e-brake cables don't keep the backing plate from sitting flat. It isn't much, but they do change the measurement. Then, measure from the bench to the top of the backing plate through the center hole (for the axle) in the backing plate.
BBP plates will measure ~1.75", the SBP 10" backing plates will measure roughly 1.25"
Checking the drum or shoes won't help, you can put 10x2.5" shoes on a 10" SBP backing plate, you just end up with interference when you install the drum.
For extra fun, you can buy brand new aftermarket axles that have the 5x4.5" bolt pattern, but the SBP axle flange offset. Those have to be used with re-drilled SBP drums.
Sounds like you have a mismatch between your axles and your brakes. SBP axles have a different flange offset than BBP axles-
And what that means is that the backing plates also have different offsets. So, the backing plate for a 10x1.75" SBP drum brake set up can not be used with BBP axles, you have to use a backing plate for a 10x2.5" drum set up. No mixing and matching of axles and backing plates.
To measure the backing plate offset you want to set the backing plate flat on a bench. You'll need to hang the bottom 1/3 of the backing plate off the edge of the bench so that the mounts for the e-brake cables don't keep the backing plate from sitting flat. It isn't much, but they do change the measurement. Then, measure from the bench to the top of the backing plate through the center hole (for the axle) in the backing plate.
BBP plates will measure ~1.75", the SBP 10" backing plates will measure roughly 1.25"
Checking the drum or shoes won't help, you can put 10x2.5" shoes on a 10" SBP backing plate, you just end up with interference when you install the drum.
For extra fun, you can buy brand new aftermarket axles that have the 5x4.5" bolt pattern, but the SBP axle flange offset. Those have to be used with re-drilled SBP drums.
