Rear drums dragging

[cnorman31]

I recently did a full rebuild on my drum brakes—new pads, wheel cylinders, drums, e-brake cables, etc.—but now both rear brakes are dragging to the point that they start smoking. It feels like I'm driving with the emergency brake on all the time.

Visually, everything appears to be installed correctly, but I went ahead and disassembled and reassembled the driver’s side just to be sure. This is my first time working with drum brakes, but after watching several videos and comparing setups, it seems like everything is in the right place. So, I’m still not sure what’s causing the issue. Hoping someone with a more experienced eye can take a look and point out anything that looks off.Here are some pictures after reassembly—anything stand out?

e

 

[limp]

Did you replace the rubber hose from the body line to the lines on the housing?? These get old and reduce the inside diameter causing fluid movement problems...
The smaller shoe faces forward, Can't tell from your pic
Here is a pic of mine you can compare yours too.... MIne is from a 9" but I believe the drum parts are basically the same..
The secret to drum brakes is to do ONE side at a time to you can go look at the other side for directions...... LOL.... I still do it that way..

 

[cnorman31]

Did you replace the rubber hose from the body line to the lines on the housing?? These get old and reduce the inside diameter causing fluid movement problems...
The smaller shoe faces forward, Can't tell from your pic
Here is a pic of mine you can compare yours too.... MIne is from a 9" but I believe the drum parts are basically the same..
The secret to drum brakes is to do ONE side at a time to you can go look at the other side for directions...... LOL.... I still do it that way..

No, I didn’t replace the hose—are you referring to this one?

https://lmr.com/item/LRS-2282B/86-95-Mustang-88-Rear-End-Center-Upper-Rear-Brake-Hose

Yes, I have the smaller shoe facing the front of the car. I’m starting to wonder if the drum or shoes are out of round, because when I rotate the drum by hand, it’s harder to turn at certain points.

Also, comparing mine to yours, it looks like your parking brake lever sits further behind the shoes than mine does. Just wondering if the e brake isnt disengaging like it should. This is the passenger side without having disassembled.

 

[limp]

Is your E brake released and loosened ? Seems like the newer cars have some sort of self adjuster.... My 83 has a good ole fashioned nut and bolt affair on the brake handle
The best way to adjust new drum shoes is to tighten them as far as you can, then LOOSEN them up the same amount of clicks on both sides....
You want the shoes to just drag " a touch" when you adjust them....
make sure your E brake is Ok before adjusting. Make adjusting your E brake the very last step

 

[limp]

Yes, that is the brake line I was referring to, if its origiinal I would replace it...

 

[nickyb]

What's the drum look like? The chikneess ones are known to be out of round.
If not sure have them turned.

 

[General karthief]

Replace that single brake hose, if it still drags unhook the cable for the E brake then test drive.

 

[General karthief]

Replace that single brake hose, if it still drags unhook the cable for the E brake then test drive.

 

[Noobz347]

Or maybe...

Replace that single brake hose, if it still drags unhook the cable for the E brake then test drive.

 

[Mindseye007]

I recently did a full rebuild on my drum brakes—new pads, wheel cylinders, drums, e-brake cables, etc.—but now both rear brakes are dragging to the point that they start smoking. It feels like I'm driving with the emergency brake on all the time.

Visually, everything appears to be installed correctly, but I went ahead and disassembled and reassembled the driver’s side just to be sure. This is my first time working with drum brakes, but after watching several videos and comparing setups, it seems like everything is in the right place. So, I’m still not sure what’s causing the issue. Hoping someone with a more experienced eye can take a look and point out anything that looks off.Here are some pictures after reassembly—anything stand out?

e

Are those drum brake shoes from LMR? They look like they have a lot of meat on them to grab really well.

 

[cnorman31]

Finally had some time to work on this. I replaced all the rear brake lines and the master cylinder, bleed, then took it for a drive—still getting brake drag. I can even hear them squeaking while driving. When I got home, I jacked it up and tried turning the wheels by hand, and the rears were really hard to turn. The fronts have some drag too, but not quite as bad. Also, when bleeding the rears, I wasn’t able to push the pedal all the way to the floor. I’m stumped on what’s causing it—could it be the proportioning valve?

 

[AeroCoupe]

Have you replaced the rubber line between the hard line on the body and the rear end? Have you verified that the e-brake system is fully functional?

 

[cnorman31]

Have you replaced the rubber line between the hard line on the body and the rear end? Have you verified that the e-brake system is fully functional?

Yes, I’ve already replaced the rubber line. I haven’t fully checked the e-brake yet—mainly because I really don’t want to tear the brake assembly back apart. It does have a brand new cable though. What’s the best way to test it? Should I disconnect the cable from the lever and see if it still drags? Also, with the other symptoms (front drag and not being able to push the pedal to the floor when bleeding rear), wouldn’t that point to something else?

 

[cnorman31]

I’m also wondering if the drums might be out of round. When I spin them by hand, they’ll free up after a few turns but then progressively get harder to turn again. I got these from LMR a few months ago, but I’m considering grabbing a set from the local parts store to see if it makes a difference.

 

[AeroCoupe]

As the General mentioned several posts earlier, I would pull the drums and disconnect the e-brake cables there. If the dragging stops then you know somewhere in the e-brake system there is a problem.

You can pull the drum and take them to a shop that turns them. They should be able to check and see if they are machined correctly.

 

[General karthief]

The front rotors drag a slight bit anyway but the rears should not, yes check the part brake cables,

 

[limp]

I don't see how rotating your drums by hand could cause tightening of the shoes... The adjuster works by applying the brakes and/or the E brake..... If the problem is not in the adjuster I would look at the MC possibly... perhaps its not allowing the fluid to retract so with each pump of the pedal the pressure increases?? Is this a drum/disc MC?? NOT telling you to run out a buy a new MC, just tossing out idea's here...
I too like the idea of loosening or disconnecting the E brake cable to see what happens...

 

[AeroCoupe]

Did you get the adjusters on the correct sides?

 

[cnorman31]

I don't see how rotating your drums by hand could cause tightening of the shoes... The adjuster works by applying the brakes and/or the E brake..... If the problem is not in the adjuster I would look at the MC possibly... perhaps its not allowing the fluid to retract so with each pump of the pedal the pressure increases?? Is this a drum/disc MC?? NOT telling you to run out a buy a new MC, just tossing out idea's here...
I too like the idea of loosening or disconnecting the E brake cable to see what happens...

I don't see how rotating your drums by hand could cause tightening of the shoes... The adjuster works by applying the brakes and/or the E brake..... If the problem is not in the adjuster I would look at the MC possibly... perhaps its not allowing the fluid to retract so with each pump of the pedal the pressure increases?? Is this a drum/disc MC?? NOT telling you to run out a buy a new MC, just tossing out idea's here...
I too like the idea of loosening or disconnecting the E brake cable to see what happens...

It’s not that they keep getting tighter as I turn them by hand—the resistance stays about the same—but there are spots where they get easier to turn and then harder again, back and forth like that. If that makes sense. That’s why I’m thinking the drums might be out of round or something. And yes, it’s a drum/disc master cylinder, just the stock replacement that LMR sells. It’s brand new.

 

[Noobz347]

Do you own a dial indicator?

Put the drum on the lugs [backwards] to spin it and check it for round.

Even if you don't have a dial indicator, you could use a small vice to hold a metal ruler or straight edge.


Just to illustrate how you might setup a straight edge/indicator. Measure the shoe lands instead of the hub:


View: https://youtube.com/shorts/BCP49GNAufE?feature=shared