Can't find new rear hubs for '74

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crazy4offroad

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It could be a combo of needing to have the drums turned and the hubs not being fully seated. Today he was having a helluva time getting them seated.
You need a new mechanic. Sometimes a new set of eyes and experiences will spot something overlooked. There really shouldn't be this much trouble with this job.
 

Erik

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Agreed! He’s always done a good job for me, but this one has not worked out at all.
 

bucket

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it sheds a ton of rotational mass and unsprung weight. so it will improve rear suspension performance, mpg and acceleration; albeit may not be huge. they are better performing (especially when wet or with a load in the bed) and much easier to work on. if you live in an area with mud or salt or any contaminating debris, they clear that stuff way better too.

there really aren't a ton of reasons to not, other than some cash and losing originality.

There was an article on the internet somewhere, a guy cross drilled his brake drums. I think it was a Dart or something, but it was 4 wheel drum. He said it seemed like a good improvement for shedding heat/ brake gas/ moisture) etc.

This doesn't really apply here, you just made me think of it, lol.
 

Erik

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Problem solved. As y'all thought, the new drums were out of round. Got them turned and everything is working great now. Thanks for the advice, and lesson learned. Always turn new drums!

As to my original question about finding hubs, I couldn't find any at a local yard but found them on car-part.com, from a salvage yard in Missouri. If you happen to need new hubs, be aware that there are two parts out there that look very similar but aren't identical. The hub for a C20 with 13" brakes takes 9/16" studs and looks like this:
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One of the hubs I received from the junkyard takes 1/2" studs and looks like this:
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I'm guessing the second one might be from a 1/2-ton. The only difference is raised metal parts the studs pass through are more square for the C20 hub and more round for the second one, and of course the stud size. Everything is else is identical. Just an FYI.

Oh, and I also have a couple spare hubs now if anyone needs them.
 

bucket

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Does the hub for 1/2 inch studs have GM marked on it too? I thought 1/2 in studs was a Dodge thing.

Oh, or maybe a pre-73 truck.
 

CSFJ

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Semi float?
semi float don't use hubs like that. They're built with c-clips to retain the axles like the half ton stuff. Drums slip over the axle flange.
 

highdesertrange

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1/2 tons never had full floating axles. highdesertranger
 

Erik

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I'll have to take a closer look at the markings. Maybe it isn't GM at all. I'd send it back to the junkyard and try to get my money back but it isn't worth the shipping costs. These things are heavy.
 

roundhouse

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One set
Might be dual wheel
And the other set single rear wheel ?
 
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