68 Camaro Rear Disc Brake & Differential Problem

[Judges4u]

Folks,

My friend's 68 has some issues with the rear disc brakes dragging with a differential clunking noise. Rear drums converted to disc brakes by former owner.

When turning the wheels to the right or left moving very slowly, or moving forward or backwards very slowly, the rear wheels drag in a pulsating manner and you can hear a loud metallic noise coming from the The 12 bolt differential. I thought perhaps the rotor(s) were warped.

I removed both wheels and inspected the disc brake conversion kit parts. I noticed the shims are mounted on the outer side of the caliper holding brackets vice the inside where the spacer grooves are for installing the shims (they look like Summit Racing brand kit brackets) so that is one problem where axles will have to be pulled and shims installed correctly. The three bolts that hold the caliper brackets to the axle tubes on each side were not torqued enough creating way too much movement in the calipers while depressing the brakes so I tightened to decrease about 75% of the play / slop. With wheels back on, the issue was still not solved. At higher speeds I didn't notice any differential wining or howling. I initially thought perhaps the former owner didn't add the posi-lube, maybe causing this rear brakes to pulsate / drag during slow movement and turning of the wheels and moving forward or backwards. I was also thinking badly warn axle bearings.

Any ideas what else may be causing the issue? I'll be pulling the axles this weekend.

Thanks in advance.

Jim