I called ECI (
www.ecihotrodbrakes.com) about this for my 41 3/4 ton
They told me to check my bearings for there part #'s
If the outer bearing ends with a 01 and inner bearing with a 52
There disc brake kit will fit.
It's a complete kit, mounts, caliper,rotor,hub,bearings, Only drawback is it's 5 lug!