Jump to content
Fowl Jeff

Found a brake drum solution

Recommended Posts

Hello All,

It’s been ages since I posted to the forum, although I follow it regularly. So I wanted to share a solution I found for my brake drums – specifically 11” diameter drums, 2” width, and a 5x4.5 bolt pattern. As many of you know, these are hard to find and very expensive!

This was a journey of countless hours that turned into days and then weeks, with many promising leads that turned into dead ends along with a fair share of mistakes. A couple notable things I tried that didn’t work include:

·         I came across a manufacturer who was willing to make drums for me, but the minimum order size was well over $2,000. I called Gary up at Roberts to see if he’d be interested in going in with me, but even then the price per drum was prohibitive.

·         I contacted a company called “J&G Drum Relining” about relining my existing drums, but the price for doing this was almost $400 each.

·         I bought and subsequently returned several drums – including blank ones that let you drill out your own bolt holes - that looked like they might work. In each case I hit a show-stopper: center (hub) hole too large/small, overall width incorrect, and so on.

Finally I came across a post in a car forum that gave me an idea. Instead of looking for an impossibly narrow 2” drum to fit inside of the backing plate, what about a wider, flared drum that fits around the outside? Bingo! I found one that did the trick after a bit of modification. It’s a finned drum by Raybesto, part number 2955R. It has an outside diameter of 13.62" but the all-important inside diameter is 11”. It has a 5x4.5 bolt pattern and 3” center hole. They’re available on Rockauto for $35 each plus shipping. And now for the details 

Edited by Fowl Jeff
clarification

Share this post


Link to post
Share on other sites

First, I had to remove the hubs from my old drums. It goes without saying: be careful! I dimpled the rivets with a punch, drilled them out carefully, knocked the heads off, and tapped them out. Turns out the rivet holes in the hub are 5/16 inch.

Original drum and hub.png

Share this post


Link to post
Share on other sites

Now for the new drums. As you can perhaps see from the stock photo, they have an inner lining and just the five bolt holes, but no holes for the rivets. Sadly, the toys I’ve picked up along my truck journey did NOT include a drill press.

Raybestos 2955R Inside.png

Share this post


Link to post
Share on other sites

Being the clever rascal that I am, I laid the original hub in the new drum and the center hole fits PERFECTLY (to the right in the picture). Now just line up the original bolt holes in the hub with the existing ½ inch holes in the drum, thread in the lug bolts, and tighten firmly to lock the hub in position. With this done you can use the existing rivet holes in the hub as a guide and drill out the five holes with a 5/16 bit. My shoulder's a bit sore from patting myself on the back.. :-)

Modifying New Drum.png

Share this post


Link to post
Share on other sites

At this point there’s still one large challenge. The inner lining on the new drum is about 3/8” too wide and will rub against the backing plate. Fortunately my brother had an old Ammco  brake lathe he let me borrow – in fact the dang thing is still taking up space in my garage. So after watching a few youtube videos, practicing with it, and ruining a few bits along the way; I was able to shave a chunk off the inner lining. Important tip: you can’t do this with the hub bolted to the drum – just mount the new drum into the lathe and get it properly seated so there’s no wobble. PM me if you have any questions about this.

Finally, I was ready to bolt the hub to the drum. There’s not a lot of room inside the drum and if your bolts stick out too far they’ll hit the steel tube that runs between the two brake cylinders. So for this I bought some grade 8 stainless steel low profile 5/16 bolts. I found them on a website called boltdepot.com. Here’s what the finished product looks like.

Assembed New Drums.png

Share this post


Link to post
Share on other sites

Excellent work!!!  I ask if riveting the hub to the drum is necessary... On newer brake drums, the drum is held to the hub by the lugnuts and lugstuds clamping the wheel and drum to the hub, with the addition of a push nut on one or two lugstuds to keep the drum from falling off when servicing the tires.  This may also work for this vintage application :cool:

Share this post


Link to post
Share on other sites

I have drilled the rivets out of my stock drums and have no issues. The brake shoes hold it on while changing tires with no issues. 

I drilled mine out when switching to wheel studs instead of bolts. With the drum off, it's also easier to pull the hub with a 3 jaw puller.

Share this post


Link to post
Share on other sites

Hi Guys,

OK so as for the rivet holes - no argument from me! I agree they're not necessary. That said, I'm content with how my drums turned out. If you look carefully at the pictures above, notice that I left one of the bolts protruding about 1 1/4 inches and ground the threads off. That's because the original drum had a pin here for hanging the wheel on while threading in the lug bolts, and I wanted to emulate this. Plus I figured the original hub was fastened to the drum anyway.

Another mistake I forgot to mention: I tried using shims instead of cutting the inner drum lining. Found a company to make the shims for me and they even drilled out both sets of holes (1/2 and 5/16). BUT - this introduced a couple problems: (a) the lug bolts were too short - which is especially an issue on the reverse-threads, and (b) the farther the hub is away from the drum itself, the more tendency it has to get slightly misaligned and wobble. So I cut the drums and threw away the shims. As I recollect the past few months, I think I did more things wrong than I did right!

Hey Fiddy - I'll give it some thought. Given the posts above about the rivet holes not being needed, that basically leaves you with only needing to cut 3/8 off the inner lining. I suspect any shop that can turn brake drums could do this for you. But if you really need help feel free to PM me and I'll do what I can.

- Fowl Jeff

Share this post


Link to post
Share on other sites

Thanks, Fowl Jeff for this information... I've been looking for a long time for new drums.  I look forward to fixing my truck and having decent brakes, after a few years of them being marginal.  Brought the old girl ("Darla") out of the barn last Sunday and the brakes went to the floor.  No more putting it off, now.  Thanks again.

Share this post


Link to post
Share on other sites

Any part number that would  fit the 10" drums on cars?

Share this post


Link to post
Share on other sites

Very good information Jeff and thank you for sharing. I have had this subject in the back of my mind over the years, thinking of when my drums will finally become too thin to use.

 

I would recommend riveting the drums to the hubs. This ensures that the lug screws are not absorbing the shear of the drum mounting plate as you brake.

 

5/16" bolts in the rivet holes are a plus over nothing, but the bolts still do not fit tight enough within the holes to make it a completely solid assembly. When rivets are installed, the shank is compressed, which completely fills the holes and any imperfections within, eliminating any slop potential. I believe that this is the reason they were built this way from the factory.

 

If you end up going this route, check the drums on your brake lathe after riveting to ensure trueness.

 

I don't think it's hard to do if you have the correct tools, but I am unsure what type of rivet gun, dies, and where to obtain. I have had little success in finding tools in the rivet dept.

 

A friend of mine has a '65 Chevy truck with 4-wheel drum brakes, and lost two wheels on the road at different times. The lug studs were sheared completely off. His truck originally had them riveted onto the front hubs and rear axle flanges.

Share this post


Link to post
Share on other sites
24 minutes ago, John-T-53 said:

5/16" bolts in the rivet holes are a plus over nothing, but the bolts still do not fit tight enough within the holes to make it a completely solid assembly. When rivets are installed, the shank is compressed, which completely fills the holes and any imperfections within, eliminating any slop potential. I believe that this is the reason they were built this way from the factory.

 

Wonder if anyone on the forum has done the rivet replacement?.

 

After a quick interweb - (Rollins (tv show) sucks, my opinion, Texas is fine)  -search it appears the tools to do such a size solid rivet are available But not cheap and not readily available at the local auto repair parts places to loan! 

My rivets were all ground off when I purchased my 50 Ply. 4 dr. but have not been any problems except when installind wheels (dual pattern) that do not rest on the centers or on missing locating pins. Can be a rear pain at times!

 

DJ

Share this post


Link to post
Share on other sites

Jeff,

 

I purchased the recommended drums and had the flange machined 3/8" as directed.  Everything is great until I tighten the hub nut.  The tighter the nut, the more the drum rubs and with sufficient torque (about 40 ft-lb) the drum locks.  I installed a homemade 1/8" spacer plate between the drum and hub.  This helps, but doesn't solve the rubbing/lock-up problem.  I've tried placing colored chalk on various surfaces to determine what is rubbing against what, but with limited success.

 

I'm considering increasing the space thickness to 1/4" or having the drum flange machined further.  Any suggestions from anyone before I give the machine another $70??

 

Thanks

 

John

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.

Terms of Use