Strange situation on rear brakes - 67 Barracuda

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GlennB4u

GlennB4u

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Hey all... I have this strange problem. My 67 Barracuda has a 8.75 rear with SBP wheels to match the SBP fronts. The thing is, the rear brakes are not 9in or 10in like I would expect, but 11in. I'm not sure what the combo is but you can see that the drums appear to have been drilled and they hit the backing plates, so someone placed 2 washers on each stud for clearance. My question is... do you think I can fix this issue by putting on 9 or 10in brakes/drums and just tossing these monsters? Or maybe get some BBP axles and change out the wheels...

Thoughts?

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Oklacarcollecto said:
Wow!! The shoes look like 10". Post a measurement of the inside of the drum.
Click to expand...

You know, I looked at the image with the tape measure and didn't burn that 1st inch, so I'm sure you are correct and they are 10in. I'll have to get back to you with that exact measurement.
 
Looks like what somebody did was redrill B body drums to the A body pattern. That's why they had to put the washers in. The B body backin plates have a different offset. You probably need to find some A body drums and you'll be good.
 
RustyRatRod said:
Looks like what somebody did was redrill B body drums to the A body pattern. That's why they had to put the washers in. The B body backin plates have a different offset. You probably need to find some A body drums and you'll be good.
Click to expand...

That is the reason I asked about the brake shoe width. The picture is hard to tell for sure but the shoes look wider than the 1 3/4" that the a body uses. The self adjuster pictured didn't start until 1969 but will work as a retrofit if you use all the parts.

The big problem is that the rear 10" brake drums that the car would have come with are no longer available at the parts stores.
 
I'm mystified. The tape reading LOOKS like a 10" setup. Do the shoes fit the drums???

If the drums and shoes are the right size, I'd just find someone to turn some off the back of the drums and RUN them, assuming the drums have not been turned oversize
 
Where do the drums hit? That huge outer ring could come off and not hurt a thing

I cannot see in your bottom photo........how far do the shoes come to the INNER wall of the drum? Now, you'll have to have them turned, as the shoes will have "worn in" on the drums, but if you can clear the outer problem on the backing plates, will the shoes clear the inner part?

Also, you need to have someone with a "drum mic" (or other accurate measuremen) check that the drums are not too far oversize. "the standard" default oversize used to be .060
 
Just a wild guess... Someone put the misfit brakes and drums on the original backing plates because they cant find the correct drums available anywhere.
 
RedFish said:
Just a wild guess... Someone put the misfit brakes and drums on the original backing plates because they cant find the correct drums available anywhere.
Click to expand...

I think your right. So they rub the backing plate? Put a few more washers on. Good to go.
Just kidding don't do that.
Can you really not get 10" replacement drums and the correct shoes? Or did someone just cheap out and cobble together what they had laying around.
Last new set I bought was in the early 90s. Been using larger B&C body brakes since then.
 
Looks like brakes are 10" and drums are 11". Do the rear brakes even work?
 
ssba said:
I think your right. So they rub the backing plate? Put a few more washers on. Good to go.
Just kidding don't do that.
Can you really not get 10" replacement drums and the correct shoes? Or did someone just cheap out and cobble together what they had laying around.
Last new set I bought was in the early 90s. Been using larger B&C body brakes since then.
Click to expand...

The correct rear 10" drums are obsolete and impossible to find unless you get extremely lucky. Some of the part stores no longer have the front drums available either so it appears they are also headed the same way as the rears.
 
Im going to give my guess. The drums and shoes look like D100 stuff. 11x2.5 but, that backing plate is too narrow. Have the axle tubes been cut? The early D100s are 43 inch from perch to perch. Maybe someone cut it down to Abody width.
 
11"x2.5" was a standard Police Special Option rear drum and shoe size in the early and mid 60's, at least for B-bodies. So that is a possiblitly that needs to be explored.

What the OP needs to do next is to remove one or both of the shoes and lay them inside the drum and see if the arc of the shoe is very close to the arc of the drum. It will be obvious at that point if these are 11" shoes or 10" shoes; 11" shoes would lay in like a glove. They do look like 10" shoes but this does need to checked to understand the set-up better. A pix of the shoes in the drum would be good to see.

It looks pretty certain that the backing plates are for 10" from the original set of pix.
 
my5thmopar said:
Im going to give my guess. The drums and shoes look like D100 stuff. 11x2.5 but, that backing plate is too narrow. Have the axle tubes been cut? The early D100s are 43 inch from perch to perch. Maybe someone cut it down to Abody width.
Click to expand...

It appears to be small bolt pattern when you look at the drum as it has been re-drilled..
 
Alright... I removed the washers and replaced the drum. It rubs as expected, but just barely as seen by the shiny parts of the drum and backing plate. I think I'm egoing to grind down the ridge on the backing plate until it stops rubbing. OR - Does anyone think I can buy all parts necessary to replace these drums/shoes that would work with my current backing plates?

By the way - thanks for taking the time to give me input.

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By the way, the rear brakes seem to work fine although I have not yet had this car moving fast enough to tell. The parking brake works fine. After pulling the drums off, I just don't trust them.
 
Oklacarcollecto said:
It appears to be small bolt pattern when you look at the drum as it has been re-drilled..
Click to expand...

Agreed but, looks like was LB and drilled to SB, look at post 10 picture. See the 1/2 inch stud holes. What do ya think? Not arguing, just trying to help the guy out. Craig
 
The a body axles have a shorter distance from the wheel mounting face to the
housing flange face than the donor brake parts car had. These axle shafts weren't meant to hold 2 1/2" shoes. This is why the washers were required to make up this difference.
You could change to large bolt axles and the brakes would fit correct. But your wheels would need to be large bolt pattern also.
Is this a 8 3/4 or ?
If you are working on a 8 3/4 It would be a good time to change to big bolt pattern. Otherwise
You need to get those brakes off of there.
 
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