DieselVeins

When I put the truck in reverse, start to back up then apply the brakes, I here and feel a grinding. I already replaced one bad set of rear brakes because I had an axle seal wear out and my drum was full of gear oil. However when I back up and hit the brakes I still hear the grinding. It doesn't seem to happen at all when I am going forward. I had both rear tires off the ground and put it in reverse hit the brakes and didn't hear it. Also I couldn't hear anything when I would turn the axle by hand either direction. Any help would be great.

KATOOM

A grinding differential loud enough to hear over the noise of these engines would mean something serious. Just be checking the differential fluid should reveal lots of metal suspended in the fluid if that was the case.

Is it possible that you installed the drum brake assembly incorrectly and its potentially pushing components against the drum in the reverse direction.....?

Have you tried using the E-brake and seeing if the noise is still there?

DieselVeins

I don't really think the problem is in my differential cause I only hear it when I brake in reverse. I put the drum on correctly and don't think the problem is in my brakes because he noise is the same as it was before the new brake drum, I have not tried backing up with the e-brake on.

NJTman

A polished brake drum will cause this issue. Check the drum you did not replace for a mirror surface. I'd so, have it machined and sand the shoes rough again.
Check your front brakes as well