Ok, I'm gonna ask here for my brake-problem witch keeping me busy the last 8 months:

Car: Chrysler Newport 1971, disc/drum (11 x 2,5 inch)
Problem started with replacing the rear brakeshoes. Brakes kept dragging, however I adjusted them. First only the passengerside, later also the drivers side.
Trying to solve the problem I did:
- new mastercylinder (same as the old one)
- new wheelcylinders
- new rearbrake hose
- new brake hardware
- new brake fluid
As far as I can think of and see: no hydraulic issue. Shoes retract full back to anchorpin after using brakepedal. Car stops very good but rear drums get to hot to touch after a few miles.

So, what did I check next?
- backingplate
- wheelbearings
Seems all OK.

Last thing I did:
- had the linings on the shoes replaced, Linings are a bit thicker now and primary and secundary shoe have the same thickness
- drums are turned
Still dragging...@#$%^&*

What I've noticed is this: both wheels of the ground, brakes adjusted, to a very very slight drag, but when I put the wheels on and tighten the lugs: much drag !! Losen the lugs just a bit: drag is almost gone !! What ??? This is also when I put the lugs just on the drums(without the wheels on)
To make it more complicated: when I set the parkingbrake a few times, drag is gone again. But then I hit the brakepedal a few times and the drums are stuck again.
Also when brakes are free and start turning the wheel by hand, forward and backwards, after 10 to 20 turns, dragging is coming back !! without touching the brakes at all..
I don't know what to do anymore, checked and double checked everything what I could think of..

Ofcourse I've been searching the w.w.w. about this and it seeems that I'm not the only one with this issue..

For those who are interested I also put this on FCBO but unfortunally no solution yet...

http://www.forcbodiesonly.com/mopar-forum/threads/rear-brake-is-driving-me-nuts.25496/

Maybe there's someone here who has the "egg of Columbus"

Luigi

When the rear brakes are stuck, loosen the front line nut on the MC until a little fluid runs out...if this releases the drum(s), there is residual pressure remaining in the circuit when the pedal is released. Could be the MC pushrod is out of adjustment.

Thanks, but also checked that, pushrod is OK..

You turned the drums, did you also arc grind the new shoes?

Have you driven the car using the brakes a number of times. Then pulled the drums to check to see if wear pattern on shoes is fairly consistent across the shoe surfaces.

I did like John's initial response.

Check to see that the shoes aren't to wide. Dragging when you tighten the lugs is a sign of the drum rubbing against the side edge of the shoe.

As far as the tightening of drag with the lugs on I had the same issue with my 68 gmc, took the die grinder with pad to the outer edge of shoes and just smoothed the edge of lining a bit and issue went away seems when they turned the drums a small taper was left near the were the face and shoe run meet( or the azone shoes were a little off) fixed that issue for me previously I had always smoothed the leading and trailing edge on my brake shoes a bit,,, use to come that way but not anymore..

Had the same problem with my 68 Charger, the shop didn't turn the drum all the way to the corner of the drum, causing it to drag when it was tight.
Be sure you didn't swap the self adjuster mechanism and they are tightening while driving forward instead of reverse.

Problem lays on the drum contact..by tightening the lugs..the drum is contacting either the shoes or the backing plates..is it the right drums or backing plates..or even the right shoes..try using a different brand..

what they said, you wouldn't still have your old shoes would you?

I got new shoes from Rock Auto: https://www.rockauto.com/en/moreinfo.php?pk=297366&cc=1066317&jsn=308

Because the shoes kept dragging I took them ( shoes ánd drums) to a machineshop to have a look. They adviced me to remove the linings and replace them with a little thicker and softer ones. They also turned the drums to match the shoes (with new linings on them)

About tightening the lugs: sometimes I can tight them up and the drum turns free, other times the drum turns free for a while but then starts dragging after some turns on the wheel. When I losen the lugs at that time, drum spins free again. I edged the shoes on top, bottom ánd the sides.
So, the shoes touching the innerside of the drum ?? I don't think that but??

Afterall: I cán get the shoes adjusted so the drums spin free, also with the lugs tight but after al while drag comes back even without touching the brakes !

Could it be possible that the linings are to thick now? I must say that I have to turn the adjusters at the bottom allmost fully in..

How about posting a picture of the brakes you have installed. Maybe we can see something you don't. A second set of eyes never hurts.

It the old days brake shoes were ground to fit the drum called arcing. Sounds to me it`s time for new drums.

There should be a mark..a dragging mark somewhere that shows its rubbing..either at the face of the linings or the edge of the lining shoes..either the rear towards the backing plate or the front rubbing the drum.

Ok, here some pics:

First, old (in fact new) shoes, adjusters not installed yet:

[img]https://www.dropbox.com/s/3kr5bny8zi0e6fh/Old%20shoes%201.JPG?dl=0[/img]

Second, same shoes with new linings:

[img]https://www.dropbox.com/s/lcc5cxt4mydhraa/New%20shoes%204.JPG?dl=0[/img]

Last, should I file of more?

[img]https://www.dropbox.com/s/p04g64b4o0b0lla/New%20shoes%205.JPG?dl=0[/img]

Luigi

From the pics it looks like the metal part of the shoe may be hitting the inside of the drum? Also IMO, I would replace the return springs or at least close them up some and close up the clip on the e brake lever.

Sure looks like scrape marks on the outside edge of the metal part of the shoes. I'd have stayed with the original new shoes rather than the reline.

Oh yeah..the markings on the metal shoes show the rubbing marks..those are the wrong shoes too wide ..try another brand

It also could be the drums if you bought them new also..something is too wide (shoes)or not wide enough (drums)

Update: the markings on the metal side of the shoes, were made by the machineshop. They had to make the linings smaller to fit on the shoes..

[q uote=Luigi]Update: the markings on the metal side of the shoes, were made by the machineshop. They had to make the linings smaller to fit on the shoes..


[/quote ] What the Frick, make the linings narrower to fit the drums No Good I'll bet your linings are either 11.0 inch by 2.5 inch wide or 11.0 by 3.0 inch wide with the same size drums, correct? There are several different versions of those size linings and shoes for the different years of the larger diameter 11.0 inch brakes
I know your across the pond which makes it a lot more difficult to get the correct parts for our old cars made here in America, it ain't like you have 14 different local part stores to go to pick parts from like here I would want you to get the correct parts now instead of gerry rigging those parts like they are now