Correct drum for 9" drum brakes

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Jayman62

Jayman62

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My 66 Dart had swedged lugs to the drums. The old drums were toast and I removed the drums from the hub via drilling. The new drums I purchased hit the bottom knurled section of the new studs I purchased, Dorman 610024 (they hit the old studs as well). Meaning the drum cannot sit flush against the hub. What's the deal, is it the wrong stud or do I have the wrong drum? Does the correct drum have larger holes to fit over the stud? If anyone knows the correct part number for the studs and drum when converting from swedged studs I'd appreciate it.

Thanks
 
I would double check the drums are correct. Check the center hole and make sure it is the correct size for the center of the hub, as that's how the drums locate. If they're correct, you're going to have to open up the wheel stud holes a little. I've never seen that though and have replaced a LOT of drums. They normally come with over sized stud holes for that very reason.
 
I wonder if it's possible you got the wrong studs? Maybe the splined section is too long?
 
Throw a couple washers per lug and the nuts then torq them down, that should seat the drums onto the knurls.
 
I'm wondering if they maybe gave you disc brake wheel studs? Those have a very long knurled section. Can we get a picture?
 
RustyRatRod said:
I would double check the drums are correct. Check the center hole and make sure it is the correct size for the center of the hub, as that's how the drums locate. If they're correct, you're going to have to open up the wheel stud holes a little. I've never seen that though and have replaced a LOT of drums. They normally come with over sized stud holes for that very reason.
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Center hole is spot on, my first thought was to enlarge the holes as they are not far off, is that an acceptable practice?
 
RustyRatRod said:
I'm wondering if they maybe gave you disc brake wheel studs? Those have a very long knurled section. Can we get a picture?
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Here's the ones I purchased. These are supposed to be for front drum 9".

stud.jpg
 
If the splined area fits the hub, the length of the spines section shouldn't keep the drum from sitting flush with the hub. If the hub has been drilled at some point and oversize studs were installed, that could cause that problem. Either way, I'd enlarge the drum hole just enough to let the drum pass over the studs and re-swedge. Then put the assembly on a brake lathe (with good bearing races) to make sure everything is square and not out of round. Before you get too involved, I'd verify that the outer bearing races fit snug in the hubs. That's a very common area for problems on 9" brakes.
 
cudamark said:
If the splined area fits the hub, the length of the spines section shouldn't keep the drum from sitting flush with the hub. If the hub has been drilled at some point and oversize studs were installed, that could cause that problem. Either way, I'd enlarge the drum hole just enough to let the drum pass over the studs and re-swedge. Then put the assembly on a brake lathe (with good bearing races) to make sure everything is square and not out of round. Before you get too involved, I'd verify that the outer bearing races fit snug in the hubs. That's a very common area for problems on 9" brakes.
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Yes the spline of the studs do fit the hub and appear never to have been drilled. I'm starting to like the idea of just reaming out the drum holes a bit. Thanks for the suggestions.
 
There's no way IN THE WORLD I would ever reswedge a drum. There's absolutely zero need. The one and only reason the factories did this was to keep the drums from falling off going down the assembly line. The drums on A bodies are 100% hub centric. They don't need to be swedged.
 
RustyRatRod said:
There's no way IN THE WORLD I would ever reswedge a drum. There's absolutely zero need. The one and only reason the factories did this was to keep the drums from falling off going down the assembly line. The drums on A bodies are 100% hub centric. They don't need to be swedged.
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I didn't want to say anything, I appreciate someone willing to answer my questions but I agree I'd never re-swedge the drums, unless I sold my car to my enemy. Took me a while to drill the old ones out.
 
RustyRatRod said:
There's no way IN THE WORLD I would ever reswedge a drum. There's absolutely zero need. The one and only reason the factories did this was to keep the drums from falling off going down the assembly line. The drums on A bodies are 100% hub centric. They don't need to be swedged.
Click to expand...
If that was the only reason, they would have just used one of those washer clips like they used later on rear brakes. After all, Mopar didn't sell just the front drum as a replacement. Only a hub and drum assembly. No assembly line problem with that.
 
Update, the Dorman 610024 is pretty much a exact duplicate of the original studs in my hub, about a 1/4 inch longer and well much shinier (grin). I did find that the studs basically all but fell out with little pressure so I wound up spot welding them to the hub from the back side. I also reamed out my drum stud holes, not as perfect as I wanted but will do. Thanks for the help guys.
 
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