Wrong 10" Rear Drums?

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Hankrebel

Hankrebel

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I bought what I thought were rear 10" drums from Rock Auto.
All brake hardware and shoes installed with no issue.
Even the drums went on and were flush at the hub and spin freely.
I put the wheels on and drop her off the jackstands.
Put her in reverse and she wont budge an inch.
I gave it a little gas and I can hear the drums rubbing against something.
Jack her back up and remove the wheels.
Dums pull off fine but I can see where the drum lips is up against the backing plate and grinding/rubbing.
I can also see the rub marks on the drum lip and inner surface.

What gives? I measured the the old drums total width - 2 2/4
I measured the new drums total width - 3 1/4

You can see from the pictures the drums are a lot larger than the old ones.
By looking at how much is rubbing, I can probably get a shop to lathe off about 1/8 inch on the lip and inner surface. But if that doesnt work, Rock Auto wont take the drums back.

Any suggestions?

160BEECC-1CBD-437D-8557-2266595E4FF5.jpg

5F59C5BC-FA12-4EAA-B04A-13BD95137F3F.jpg

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Well, you got 10" drums, just too wide. Is this for an 8 3/4? They make different width shoes. I'm not sure on the specifics though, year, size width etc.

You could sell those and get the correct ones. Some folks have put washers on the stud before putting the drum on, I wouldn't do it, but I've seen it done.
 
I don't think there was ever a 2" drum -- technically, it's a 1-3/4. 10 x 1.75 is the size that the manufacturers forgot -- standard on A-body 8-3/4, but hard to find these days. Search the forums -- there is at least one source.
 
I figured it out cross referencing some part numbers and looking through Rock Auto.
The new drums are for a 71 front drum kit. I need the 10" rear drums. Good luck is Rock Auto will take these back and ship me the correct ones..
 
The wider brake drum that was sent to you was similar to the one RockAuto sent to me -- only mine was a Bendix. It didn't fit. If you want a rear drum to fit a brake shoe that is 10" x 1-3/4" wide and you have a SBP, please look at my sticky thread under "Brakes."

Probably one of the most accurate dimensions is the inside "friction surface." If the brake shoe is 1-3/4" wide, the correct friction surface width of the drum is 2-1/8".
 
G413 I literally looked at your thread about 10 seconds ago looking at the part numbers!
Thanks a bunc for the homework and part numbers.

Maybe you can help me with something else. The new studs just had pressed in on my front right hub have come loose and now wont grab in the hole. I dont want to try any kind of fix but get a new new hub. I cant find any hubs anywhere, not even rock auto.
71 Swinger SBP Scarebird front disc conversion
 
mvh said:
I don't think there was ever a 2" drum -- technically, it's a 1-3/4. 10 x 1.75 is the size that the manufacturers forgot -- standard on A-body 8-3/4, but hard to find these days. Search the forums -- there is at least one source.
Click to expand...

That's not an A body 8 3/4" drum he has though, so it's not 1 3/4"!
 
I don't know any source of front hubs, new.
A FYI: Before removing studs from the drum/hub, remove the swedge from the stud. If you don't the chances are the hub will be ruined. It is possible you might be able to find a stud that has a slightly larger knurl, and fit them in. Might have to drill the holes larger.
 

Once upon a time Dorman offered lug studs with a slightly larger spline. Probably still do.
They aren't listed for any specific application in their catalog though. You'll need to measure up what you remove and take that info to their catalog to find which stud is the fixer.
 
Following up on RedFish's comments, Classic Industries's catalog shows different studs (7/16-20) available with pictures and the knurl diameter. Two of the slightly larger knurl diameters have a little bit shorter length, but that is probably okay. The studs are only about $3 apiece, so it might be worth a try. These studs are only available in RH.

I went through this more than a year ago when some brake guy messed up my front hub when I wanted to change to all RH threads. I ended up buying a used hub/drum (w/ RH threads) from a junkyard. It was pretty rusted. I still don't know if the drum will clean up.
 
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