Bought a C7000- Anyone help?

[dooce]

So I bought a 1986 GMC C7000 last weekend. On the way home, the left rear brake seized, rotor got red hot and ended up catching fire. The rotor broke into several pieces and welded itself to the pad. I was able to put it out and limp it home, but now I am in the middle of doing the rear brakes on it. Can anyone identify the rear end for me? It would help in ordering the parts.

[dooce]

Carnage pics for your viewing pleasure.

[dooce]

I think it's 17,500 axle with oil bath bearings if that helps and anyone can give me advice on them.

[KQQL IT]

https://www.stockwiseauto.com/centri...xf42312f22689&

[dooce]

My rotor doesnt have the flange, it's 2 piece instead. I'm looking at the code in the glovebox and its code H93: Rear axle GMC 175 SG. Im surprised how little info is out there on these trucks. That code is pulling up on rockauto though so I might be sorted now.

[Robert1970C20rstbukt]

https://www.brakepartsinc.com/raybes...rt-search.html

You'll have to enter your trucks information, they show a lot of parts for that one. Seems like they go by the size of the caliper pistons and the rotor diameter, not by the brake/axle code for some reason.

[dooce]

Thanks. Does anyone know what oil to use for these bearings? What about where to pick up some of these conical washers? What a pain. If anyone ever has issues with them, just double nut the stud and pull it out, the cone washers will loosen up pretty quick. The axle was sealed with RTV, is this where the outer wheel bearing seal would typically go? I havent found one tearing this thing apart but there is a listing for one.

[C10 - C90 Bill]

I won't be much help. I didn't even know those newer trucks had Rear Discs !!

Big jump from my '62 GMC days. Air Brake, Rear Only, Drum Brakes (No Fronts).

[DieselSJ]

IIRC, the oil from the differential works its way down the tubes and that is what lubricates the bearings. Should be a seal on the back side of the hub and no "outer" seal. Where the axle bolts to the hub is usually just a paper gasket (or RTV).

[dooce]

Thanks, yeah thats what I read somewhere else. I will change the diff fluid while I'm in there and I should be good to go.

[Bigasstrux]

Why did it seize? I have had several trucks with these brakes, usually the rubber hoses deteriorate internally and hold pressure after brake application.

[KQQL IT]

We always packed a bit of grease into the the bearings.
At least dunk them in gear oil prior to assembly.

[83GMCK2500]

"Tapered dowels" are what they're called in old Mitchel manuals, also "axle stud cone"...I know they can be fun to get out, that's for sure. Looks to be several options including NOS GM ones on ebay: http://www.ebay.com/itm/like/2630527...=ps&dispItem=1