Will they interchange? I have a 1/2 ton 44 under my truck and I just picked up a 3/4 ton 10 bolt less backing plates and rotors.

I'm in the process of converting to 3/4 ton.

Every 6 lug backing plate i have seen is different than the 3/4 ton. The roters are bigger on a 3/4 ton so the caliper has to be higher up.

Yup, all the 1/2 stuff interchanges, and all the 3/4 ton stuff interchanges, but not 1/2 to 3/4, you'll need 3/4 ton caliper mounts.

Thanks for clearing this up guy's.:emb: