B-body 11" rear drums - how hard to find?

B-body 11" rear drums - how hard to find? - 04/20/13 08:01 PM

Well as I mentioned in another post I had taken apart my 8 3/4" rear axle that I had assembed years ago and couldn't remember if I had greased the bearings or not. Long story short, I did. But in reassembling it and adjusting the rear brake shoes I noticed that I couldn't really adjust them correctly as the drums (11" x 2 1/2") were out of round. That is, I could rotate the assembly and feel the wheel get harder to turn as the wheel got to a certain point, then it would get easier to turn after it got past that point.

I don't know if the drums have been turned before- they might have enough meat on them to correct this but in case they don't and I need to just get new drums- how hard are they to get? The drums I have are finned and I'd like to get another finned set. The local O'Reilly's THINKS they can get a set in- they've got it on order since it's not in stock (of course). I've got a bad feeling though that they were made 'offshore'.

If this fails, is there another source I could go to? New would be nice of course but if a decent set can't be had, I'd consider used in good shape.

Suggestions? Thanks!
David

Posted By: BDW

Re: B-body 11" rear drums - how hard to find? - 04/20/13 10:23 PM

RockAuto has them

Posted By: David_Trimble

Re: B-body 11" rear drums - how hard to find? - 04/20/13 11:56 PM

Cool- Found them- Bendix PDR0365, even has the fins on them.

Thanks!!!

Posted By: pittsburghracer

Re: B-body 11" rear drums - how hard to find? - 04/21/13 12:05 AM

Don't forget about the discount code.
137418739923866

5% off until May 12, 2013

Posted By: moparpollack

Re: B-body 11" rear drums - how hard to find? - 04/21/13 12:40 AM

Are you sure the barkers are assembled true? If you reverse the shoes they can drag. Are they adjusted so that tight? Did you measure and adjust them to fit?

Posted By: David_Trimble

Re: B-body 11" rear drums - how hard to find? - 04/21/13 01:01 AM

Quote:

Are you sure the barkers are assembled true? If you reverse the shoes they can drag. Are they adjusted so that tight? Did you measure and adjust them to fit?

The barkers? If you mean the shoe with the short pad to the front, yes they're on correct according the FSM. Otherwise, please explain?

Oh and PS- I didn't measure the width between shoews to drum width if that's what you mean. I backed off the adjustment then tightened them down to a light drag and that's when I noticed the unevenness. I can rotate the wheel forward and backward and I feel the drag but don't feel any outright binding...

Posted By: David_Trimble

Re: B-body 11" rear drums - how hard to find? - 04/21/13 01:02 AM

Quote:

Don't forget about the discount code.
137418739923866

5% off until May 12, 2013

It gets even better- didn't know about the code! Thanks!

Posted By: 52savoy

Re: B-body 11" rear drums - how hard to find? - 04/21/13 11:17 AM

Amazon.com used to sell 11" drum for $32-$35.. Bendex and Raybestos but they doubled in price.

Posted By: David_Trimble

Re: B-body 11" rear drums - how hard to find? - 04/25/13 10:27 PM

Ok got a question- got one of the drums from Rock today (the other is being drop-shipped from another location) and they're exactly like my originals except for one detail. The center hole seems to have a slight ridge on it while my original does not- it was completely flat. Is it still usable? I'm thinking that the rim won't seat flush on the drum with that ridge being there (it's about 1/16" tall- maybe less) Anyone using these drums have any problems with their rims not mounting right?

Thanks!
David

Posted By: BDW

Re: B-body 11" rear drums - how hard to find? - 04/25/13 10:50 PM

Need a pic

Posted By: savoy64

Re: B-body 11" rear drums - how hard to find? - 04/25/13 11:28 PM

original ones had the ridge at the hub...bob

Posted By: David_Trimble

Re: B-body 11" rear drums - how hard to find? - 04/25/13 11:30 PM

Quote:

Need a pic

Here you go:

Posted By: David_Trimble

Re: B-body 11" rear drums - how hard to find? - 04/25/13 11:32 PM

Quote:

original ones had the ridge at the hub...bob

Hmm- the one I pulled off did not have this ridge on it. However I can't prove that it's the original drum, either....

Posted By: BDW

Re: B-body 11" rear drums - how hard to find? - 04/26/13 01:39 AM

Mine doesn't have that ridge either.
Check your rim, does it make contact there?

Posted By: Cab_Burge

Re: B-body 11" rear drums - how hard to find? - 04/26/13 05:56 AM

All of the original Mopar OEM brake drums, regardless of size or years, had that little ridge

Maybe yours have been replaced before with some cheaper after market ones

The stock steel wheels are curved in away from where they center on the axle rings

The brake drum ridge will not, should not, be a factor on the stock wheels

Posted By: BDW

Re: B-body 11" rear drums - how hard to find? - 04/26/13 11:46 AM

Doesn't appear that way to me.

Mine have the PN and Pentastar cast in, wouldn't think after-market replacement would do that.

Either way, it sounds like it shouldn't be an issue.

Posted By: David_Trimble

Re: B-body 11" rear drums - how hard to find? - 04/26/13 12:28 PM

Quote:

Mine doesn't have that ridge either.
Check your rim, does it make contact there?

Well I'm running stock steel rims- the hub opening on the rim looks like it could make contact with that ridge. It's hard to tell as it's also got a raised portion surrounding the opening. I might have to just bolt the whole thing togther and do some checking, especially if this ridge is found on factory Mopar drums. And this drum I pulled off may very well be a aftermarket- now that I think of it, I don't recall finding the Pentastar logo cast anywhere on it.

Posted By: DoctorDiff

Re: B-body 11" rear drums - how hard to find? - 04/26/13 12:54 PM

Don't worry about it. Some drums had the ridge, some didn't.

Your wheels will fit.

Posted By: Blakcharger440

Re: B-body 11" rear drums - how hard to find? - 04/26/13 10:15 PM

Its the 11 inch backing plates that are hard to find.

Posted By: RapidRobert

Re: B-body 11" rear drums - how hard to find? - 04/27/13 06:12 AM

What about having your current shoes arced to fit your current drums? Here they do for $5 per corner/fast turnaround/good finish on the shoes. It dont seem like they take off hardly any material but I've checked before/after & way more contact area afterwards & I was surprised how little contact there was before in supposedly "concentric" drums/linings. EDIT even new stuff will be slightly out of round & have a point where there is contact at that 1 point as tthe wheel/drum rotates & even if the drum is perfect the rest of the shoe assy ain't & will have that 1 place that will make contact first

Posted By: David_Trimble

Re: B-body 11" rear drums - how hard to find? - 04/27/13 03:58 PM

Quote:

What about having your current shoes arced to fit your current drums? Here they do for $5 per corner/fast turnaround/good finish on the shoes. It dont seem like they take off hardly any material but I've checked before/after & way more contact area afterwards & I was surprised how little contact there was before in supposedly "concentric" drums/linings. EDIT even new stuff will be slightly out of round & have a point where there is contact at that 1 point as tthe wheel/drum rotates & even if the drum is perfect the rest of the shoe assy ain't & will have that 1 place that will make contact first

I might look into that to see if someone around here can arc the shoes. These are new/old shoes (new as I bought them and installed them, old becuase I bought them and installed them 10 years ago- but they've yet to see road use) So they really haven't been broken in yet.

The reason why I'm going over the brakes with a fine-toothed comb is that I've noticed in moving the car around that the brake pedal almost goes to the floor (PB, rebuilt master and booster) so I'm wondering if I've got some slop somewhere in the wheels that's causing this (as far as I can tell there's no misadjustment/slop in the booster/master cylinder/pedal assembly) So I'm being extra careful to make sure the wheel adjustments are correct.

Posted By: RapidRobert

Re: B-body 11" rear drums - how hard to find? - 04/27/13 04:18 PM

As you know to the floor ain't good. If you pull on the E brake then hit the brakes that'll quickly tell you if it's a rear brake clearance problem or not. If your brake shop has arcing equipment it made a difference on my braking with my used shoes & I'd do it with new ones too.

Posted By: David_Trimble

Re: B-body 11" rear drums - how hard to find? - 04/27/13 07:46 PM

Quote:

As you know to the floor ain't good. If you pull on the E brake then hit the brakes that'll quickly tell you if it's a rear brake clearance problem or not. If your brake shop has arcing equipment it made a difference on my braking with my used shoes & I'd do it with new ones too.

Unfortunately, when I had the body shop replace the floorpans they neglected to weld the e-brake cable guide bracket back in

Fortunately I have the bracket, I just need to get the car to the shop to have it done (among other things- hence my trying to get the car road-worthy).

I guess I can adjust the cable to take up the extra slack but I don't know if that would affect the test. I'm assuming that if after applying the e-brake and hitting the brake pedal, if I notice that it doesn't go to the floor anymore that the back brakes are the culprit? And if there's no change then I might want to focus my attention to the front brakes?

Posted By: RapidRobert

Re: B-body 11" rear drums - how hard to find? - 04/28/13 01:13 AM

The E brake expands 1 shoe so it might take 1 pump to take up the wheel cyl space created but yes you'll be able to eliminate the rear shoe clearance & I dont think the clearance would/could be that excessive (low pedal reserve yes but not to the floor). Either; air/bad booster/excessive round nub clearance/bad M/C/excessive shoe/pad clearances. I forgot what's been done/checked. On a difficult case I cap the M/C & want a hard pedal with virtually no travel (idling) if the booster/MC is bled out & functioning normal then hookup 1 half & continue on. Holler how it goes David

Posted By: David_Trimble

Re: B-body 11" rear drums - how hard to find? - 05/11/13 09:27 PM

Well I replaced the driver's side rear drum (fit just fine), then I adjusted the shoes on that drum (much easier to do so now- drag is very even). Before I did the adjustment I tried the e-brake experiment- I mashed the brake pedal a couple of times (went down to the floor every time- didn't go instantly down to the floor without resistance, but I had almost reached the floor by the time I felt any appreciable firmness) to center the shoes before adjusting them. Then I applied the ebrake as far as I could go and checked the cable- it was pretty taut. Tried the brake pedal again but got the same result- no difference. So now I'm suspecting the front brakes. I'll finish off replacing/adjusting the right rear drum then tackle the fronts to see if something's going on with them.

Will keep you posted-
David

Posted By: David_Trimble

Re: B-body 11" rear drums - how hard to find? - 06/02/13 09:45 PM

Things just go from bad to worse....

I finally got around to attempt to readjust the front brakes- in order to have some room to do it I need to turn the Charger around in the garage (small garage). But when I tried to back the car out, I found that I had NO brakes at all. The e-brakes worked though (thank goodness). The irritating thing though is that before I worked on the back brakes, at least the brake pedal worked a LITTLE. I think I can still readjust the fronts as the car sits, it's just going to be more difficult to do so.

But I'm now beginning to wonder if the front brakes are the culprit as I had first though. One thing I should mention is that some years ago when I first tore down the car (and long story short) I found that the car apparently had factory disk brakes but apparently one of the previous owners had swapped out the front disks (presumably along with the spindles) for 10" drums. I know this because A) the master cylinder/booster set - along with the lines - are specific to disk, and B) I found the proportioning valve (and it looks original), which I understand is used only on disk setups.

I'm wondering if there's a problem with the mismatched disk setup with the drums that's contributing to this poor/no brake issue? Any ideas?

David

Posted By: David_Trimble

Re: B-body 11" rear drums - how hard to find? - 06/04/13 10:48 PM

Noone wants to take a shot at this?

I'll listen to theories, ideas to try, etc....?

Posted By: dogdays

Re: B-body 11" rear drums - how hard to find? - 06/04/13 11:09 PM

There needs to be a residual pressure valve to keep the brake shoes out close to the drums. A disk brake master cylinder won't have these in the front.

R.

Posted By: David_Trimble

Re: B-body 11" rear drums - how hard to find? - 06/05/13 02:21 AM

Quote:

There needs to be a residual pressure valve to keep the brake shoes out close to the drums. A disk brake master cylinder won't have these in the front.

R.

Thanks.... I'm guessing that the residual pressure valve is part of the master cylinder (at least for the B-bodies)? If so then it sounds like I need to swap out the master cylinder for one that was used for drums, correct? If that doesn't solve my problem singlehandedly, it seems to me that it's still something that should be corrected.

Posted By: 696pack

Re: B-body 11" rear drums - how hard to find? - 06/05/13 03:25 AM

Quote:

Its the 11 inch backing plates that are hard to find.

I have a pair I will sell.