• Welcome to ClassicBroncos! - You are currently viewing the forums as a GUEST. To take advantage of all the site features, please take a moment to register. It's fast, simple and absolutely free. So please join our community today!
    If you have problems registering or can't log into your account, please contact Admin.

rear drum brake adjustment

m_m70

Contributor
Bronco Guru
Joined
Jun 14, 2001
Messages
1,769
Loc.
Prescott AZ
having weird issue with rear brakes. I changed out my bake shoes, wheel cylinders and put a new spring kit in it since it's been close to 25 years with these shoes. I have a 70 with 11" x 1 3/4" rear brake shoes. The brake job went as well as any I've done in the past until it was time to adjust..... It seems that there is some minor rubbing from something inside the drum that I can hear with the brakes adjusted all the way in. As I adjust the drums with out the wheels on I get to have have a slight drag on it but wen I put the wheel on and torque the wheels down, the brakes bind up on something and wheels won't spin at all.

I though the drums maybe out of whack so I tried a new set. Same problem.

The shoes are orientated right (less lining toward front) and sitting right up against the backing plate.

I've been messing with this for a few weeks now on the weekends and getting ready to throw in the towel (which I hate to even think about) since I've probably changed rear brake shoes in tons of vehicles over the years with zero issues.

Any ideas?? I'll post some pics tomorrow when it's light out.
 

JSBX

Contributor
Sr. Member
Joined
Mar 10, 2010
Messages
652
Did you measure the brake shoes? They may have been machined wrong or the wrong shoes put in the box. When buying new parts now a days there is no telling what you might get.
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
51,618
Exactly!
The first mistake might have been replacing the old parts based on age only. Or is that just the way you worded it, but they were in fact worn out as well?
Do you still have the old parts? Or are you one of those belly-efficient ones and all the old stuff is already tossed?
If you still have them, then at the very least you should compare new to old.
The shoes might be too wide, or the drums too narrow. Or maybe it’s just that an axle slipped out of the pocket and the bearing is binding up?
That last seems a long shot, but hey, it’s worth looking outside the box at this point.

I’m probably just a dinosaur when it comes to this stuff, but all of my drum brake vehicles are still sporting their original springs and, in some cases, their original cylinders too.
That makes some of them 60 years old this year. The youngest are 46 and still going strong.

Just checking, but it sounds like both sides are doing the same thing?
Anything else you change that could effect this?Doesn’t sound like it, but figured I’d ask.
 
OP
OP
m_m70

m_m70

Contributor
Bronco Guru
Joined
Jun 14, 2001
Messages
1,769
Loc.
Prescott AZ
The first mistake might have been replacing the old parts based on age only. Or is that just the way you worded it, but they were in fact worn out as well?
I’m probably just a dinosaur when it comes to this stuff, but all of my drum brake vehicles are still sporting their original springs and, in some cases, their original cylinders too.

I agree on the if it aint broke leave it alone but in this case I had a wheel cylinder leak which contaminated my shoes and was pulling on hard stops.

The shoes might be too wide, or the drums too narrow. Or maybe it’s just that an axle slipped out of the pocket and the bearing is binding up?
Did you measure the brake shoes? They may have been machined wrong or the wrong shoes put in the box. When buying new parts now a days there is no telling what you might get.

Shoes measure 1.825 width which maybe the problem......I ordered a second set just in case they were marked wrong and the second set came in the exact same. I may just go to orielys and see what they have and measure in store.

Hi, post a picture. Also check to make sure the parking brake cables are not frozen. Good luck
as soon as the sun comes up and some coffee is in me I'll grab a couple of pics!
Ebrake cables are good, free and backed off


Thanks for all the replies!
 

SLOWnEASY

Contributor
Sr. Member
Joined
Sep 26, 2022
Messages
517
Loc.
San Diego, Ca.
Maybe I missed it but what happens if you adjust the brakes all the way loose and then put the wheels on and try to spin? If the shoes are too wide it should rub regardless of the brake adjustment.
Also while you might see in my other posts I'm a fan of spray paint to look for rubs on moving parts. Pull the drums and spray paint the inner side of the brake drum on the wheel face, the part where the lug bolts go through not the friction surface. It doesn't have to be pretty, just uniform so you can spot a rub. Next find a bottle of liquid paper and pain the whole outer metal edges of the shoes. Put it all together and adjust. Then put the wheels on and use the engine to get the wheel to turn if needed. You don't have to turn it far, a 1/4 turn should be more then enough. Then pull the wheel and drum and inspect for rubbing. As an aside brake cleaner will remove the liquid paper when done but it really isn't necessary.
 
OP
OP
m_m70

m_m70

Contributor
Bronco Guru
Joined
Jun 14, 2001
Messages
1,769
Loc.
Prescott AZ
All the shoes measured the same at 1.825 with micrometer. Both sets of drums measured out to just over two inches (machined surface).
Taking my original drums to get turned as soon as can I find a place that still does that and the shoes arced to match. Didn't know this was such a specialty these days!

IMG_0787.jpg

IMG_0785.jpg
IMG_0786.jpg
IMG_0784.jpg
 

SLOWnEASY

Contributor
Sr. Member
Joined
Sep 26, 2022
Messages
517
Loc.
San Diego, Ca.
Looking at your pictures I don[t see anything obviously wrong. I just re-read your original post. If you are adjusting with the wheels off are you running the lug nuts in to tighten the drum up to where is it supposed to be? In theory you should be able to adjust with the drums just slid over the studs. But for the problem you are having I would try at least tightening the lug nuts to the drum to take out all the slack and see if it makes a difference.
 

Bruners4

Full Member
Joined
Jul 22, 2019
Messages
282
Loc.
1/2 way to everywhere
I make an initial brake shoe adjustment with the drum in hand. I hold the drum over the shoes about halfway, studs not engaged in the drum, and move the drum left - right to see how much clearance there is. Then move the drum away from the brake shoes and turn the adjuster star wheel to expand the adjuster. then repeat until the drum just barely fits on. Then push it all the way on, fully engaging the studs. Mount the wheel and then use a brake spoon to get the final adjustment, leaving them a little loose will allow you to verify that the self-adjusters are working during the initial test drive before getting out on the road.
I've used this quick adjustment procedure for a long time. Figured it out when doing 4-wheel brake jobs when they turned the drums and rotors, repacked wheel bearings & overhauled calipers and wheel cylinders as part of the job. I averaged 4 of these a workday working commission. Only one comeback that I can remember over the years working on brakes.
Give it a try.
 

mattyv87

Jr. Member
Joined
May 15, 2011
Messages
105
I make an initial brake shoe adjustment with the drum in hand. I hold the drum over the shoes about halfway, studs not engaged in the drum, and move the drum left - right to see how much clearance there is. Then move the drum away from the brake shoes and turn the adjuster star wheel to expand the adjuster. then repeat until the drum just barely fits on. Then push it all the way on, fully engaging the studs. Mount the wheel and then use a brake spoon to get the final adjustment, leaving them a little loose will allow you to verify that the self-adjusters are working during the initial test drive before getting out on the road.
I've used this quick adjustment procedure for a long time. Figured it out when doing 4-wheel brake jobs when they turned the drums and rotors, repacked wheel bearings & overhauled calipers and wheel cylinders as part of the job. I averaged 4 of these a workday working commission. Only one comeback that I can remember over the years working on brakes.
Give it a try.
They also sell a measuring tool to do this too. You measure the inside of the drum on one side of the tool and the other side of the tool shows an outside-to-outside measurement. Then you just set your shoes slightly inward of that meausrenent. You can get the tool new but they're a little pricey. I found one on eBay not too long ago for under $20. It was a kd tools no 278. Here is one at advance but like I said if you have some time to wait check marketplace or eBay for a used one or some times you get lucky with an NOS one. Kd tools brake shoe setting tool
 
Last edited:
Top