front hub runout

[Cav Trooper]

Anyone have an idea how much runout a M37 front hub is allowed? I have problem with a drum dragging like it is warped. I switched drums front to rear and the front drum works fine on the rear hub, the rear hub drags on the front shoes like it is warped now. I get approx. .020" runout between the studs and the hub pilot dia. Appears to be a bent hub bolt flange.

Thanks,

Cav Trooper

[MSeriesRebuild]

Any # of issues can cause dragging, no definitive answer other than simply going through the process of elimination to figure it out. One major cause for what you have can be the wheel cylinder pistons stuck and not fully retracting, have you checked that?

[Cav Trooper]

Yes, all brake components are new, the wheel cylinders are working properly. As I discoverd, I get about .020" run out on the hub bolt flange surface. I tried an experiment and place graduating shims from .010" to .015" to .020" from both sides of the run out area. With that done the drum drag is almost gone. It's slight enough that I know that is now the problem. Looks like it's time for a good hub. I could disassemble (no spindle nut wrench yet) and press the studs out then set it up in the lathe and indicate on the bearing bore and take a skim cut to true the surface. Me thinks it's easier to get another hub if the price is reasonable. I never remembered have this much fun back in the day. I forgot how dirty brake equipment is and how long it will take for the brake dust to migrate back out of my pores.

Cav Trooper

[powerwagontim]

Trooper,
I have extra hubs if you find you need one.
Tim

[Cav Trooper]

Thanks, the person I purchased the truck from had an extra hub he donated to the cause.

Cav Trooper