I tried to do a brake job on the rear of my truck today. I swapped a Mopar 8.25 rear into my 46 Dodge truck. Two issues have come up. First even with the adjusters slacked off completely, there seems to be quite a bit of drag. I can rotate the wheels by hand, but I don't remember ever not adjusting them a bit. The drums are new and of course the shoes. Anyone else had this, or do I need to go back in and look for an issue? Problem two. The new rear end has parking brakes, so I was going to use them. Unfortunately the stock (for this rear) cables were a bit too short, so I searched online and Jeep people who have lifted their trucks use another model Jeeps cables to get the needed length. I bought them. Installing the brakes today, the spring around the cable that goes inside the drum was a bit longer than the original ones. This caused the cable to bow out and prevent me being able to put the adjuster on. It was jammed completely by the parking brake cable. So I pulled the new cable and left it with nothing. My second question is what does anyone think...leave the lever for the parking brake in there, or take it apart again and remove it completely?
When I installed a Maverick rear end in my Ranch Wagon I reused the stock e brake cables but the spring on the stock cable was too long like your situation. I used a pair of side cutters and shortened the spring. Had to make several cuts being careful not to cut the cable itself so the pieces would slide over the cable. Problem solved for me.
Good question, and no...I forgot. Guess I'm going back in. I also bred the brakes with the old shoes in, so maybe the wheel cylinders need to move back some. I was pumping them pretty hard. Don't know if that could be an issue or not. Won't be without a parking brake. The stock one on the rear of the transmission is working fine. I just adjusted it, and forgot to release it when I started...couldn't rotate the rear at all until I remembered that. Works well.
That's what I was thinking of doing, but since I've got a lot of other stuff I have to do to adapt my stock parking brake lever to the rear end's parking brakes, I was thinking of just using the stock one for now. My only question is if leaving that lever in there might be a problem, or if I should remove it.
What condition are the pads on the backing plate? With drum brakes, the shoes slide on these pads on the backing plate. These need to be greased. Since most people never grease them, the brake shoes can wear deep grooves in the backing plate. These grooves can catch the shoe and prevent it from sliding correctly. So... What condition are the backing plate pads?
A lot of relined brake shoes have over size linings on them, as they figure you are running old drums that have been turned a time or two. That may be your dragging problem.
If you drive with the brakes while they're dragging ,you will , at best , hot spot the drums . hold the shoes in the drums & see if the arcs match . make sure the wheel cylinders are fully retracted . Once your cables are installed & adjusted , the spring on the end will be a non factor . How much too short are the cables , there care cable extenders available or you can fab something .
Won't be driving until I get this sorted out. I never thought about the adjustment taking up some of the spring, but I have to feel that they would be pretty tight to compensate. I'll look at that tomorrow anyway. I plan on trimming that spring back to the same length at the old one too. They were 12 inches too short on one side at least. I didn't like the placement of the box I'm using to replace the one on Jeep's for the equalizer bar, so to get it in a good place to alignment with the front lever, I need them both longer. I'm probably just going to eliminate the rear axle parking brakes for now and plug the hole. I don't need them so long at the stock one is working great. I fought with it so much and was frustrated, so I think I need to take a fresh look when I remove the parking brake mechanicals. I'll keep them for future use, along with the brand new cables. A tranny swap is in the future, just not now. Now I want to drive it.
Those pads the brake shoe sits against really needs to be flat, any dip will hold the shoe in that location and will likely hold the new shoes against the brake drum. If they are not flat, the dips need to be welded up and ground flat. You also want to make sure the wheel cylinders are not all gunked up inside. Pull one of the outer seals on the wheel cylinder away from the cylinder a bit and make sure there is no brake fluid between the inner seal and that outer boot. any fluid there means the wheel cylinder needs to be rebuilt or replaced. With the parking brake stuff removed, the top of the brake shoes should be tight against the top anchor pin. The wheel cylinders should push back in so the top of the shoes are against the top pin, that would be with or without the top return springs in place., but definitely with the return springs in place. The adjusted should turn pretty easy, if it doesn't, it either needs to be cleaned up, or replaced. The little end piece that fits over the one shoe also needs to spin freely. If either part does not function freely, the adjuster won't work like its suppose to. After you get everything on the brakes together, I usually shift the shoes side to side stopping with the shoes centered on the backing plate, before adjusting the adjuster, and then shift them again after the adjustment, the shoes should be centered on the backing plate. Adjust the shoes out so there is a slight drag you can feel when you turn the brake drum. When everything is bolted together, the tire should rotate smoothly with a slight drag. If it rotates with a tight spot, the drum probably isn't true, or something with the shoes or the springs isn't seated correctly. Gene
I was taught and then taught a lot of students to tighten the adjuster until you cannot turn the wheel and then back the adjuster off 11 clicks. This was on non self adjust brakes but the process stays the same. You absolutely have to have some drag between the drum and shoes for the brakes to work right and have decent pedal. No drag means the brakes aren't adjusted. I've probably done 3000 brake jobs in my life and 80% of those were on cars with 4 wheel drum brakes in the early 70's. I adjusted every one the wY I described. Park brakes on the rear end you would have been far better off to use the stock cables that were on the rear and make some short extensions for them unless you could find exact fit correct length cables for that rear.
OK. Finally got it. I should have stuck with my original plans, but the wheel cylinders looked dry...on the outside of the outer boot. Gave it a squeeze and out came some fluid. I already had then, which really makes me stupid... Still need to bleed, but I can't get the other side done yet. I need to move the truck out of the garage to pull the axle so I can change the studs. The wheel rotates now with slight drag, and it doesn't bind up. I guess the top was jammed a bit and not going in far enough. It would catch and then since the adjuster was fully loosened the shoe would cock and jam up. That's my theory at least. Got that side's wheel back on and on the ground for this weekend. No parking brake lever or cable, again the stock one is working fine. Thanks you everyone and especially to gene-koning for suggesting I take another look at the wheel cylinders. I can fool me once...I'll just change the damn thing on the other side.
Didn't mess around today. Swapped the wheel cylinder and the other side went together with no drama. Did the studs too. Need to adjust and bleed, then bed the new brakes. Finally time to drive again.
New shoes used to require arcing to match the radius of the drums. Some auto supply stores "used" to have brake lathes and a machine to do this. Then they fit and give full contact with the drums.
After installing the new shoes and drums, you need to press the brake pedal hard to center the shoes. They will often drag if you don't do this. If your brakes weren't bled, then you had to have missed this step.
Changed both wheel cylinders, so yes the brakes need to be bleed. The first time when I had the problem, the wheel cylinders were not changed yet, and the brakes were fully bleed. The problem turned out that the wheel cylinders were bad and didn't fully retract. They do now. So it's all just normal work...adjust the shoes, bleed the brakes, adjust again if necessary.
Sounds like you're moving along. @tomcat11 does bring up good point. The last set of drums I did, I checked the new shoes in the new drum, before installing anything. The arc was a lot farther off than I expected. I needed to drive the truck, installed them as is and checked after a few hundred miles the wear pattern was even on the shoe. Can't tell if the ends had to wear in or the shoe took an arc as it ran. If the ends just wore in the life of the shoes is probably shorter. After seeing that, I'm definitely bench checking them in the future. Coulda tried a few brands of shoes if I had the parts and checked ahead of time.
A correctly fitting shoe should touch in the middle and have a small clearance at each end. I'd have to look up the clearance but it seems like it's around 0.010 or so at each end.
Finally got things so that I could take a short drive today. Started just going back and forth in the driveway to make sure it would stop...then I did a few laps around the block. It stops at least as well as before. I need to do a better job bleeding and adjusting the brakes. Tomorrow I'm going to enlist the wife to get a good bleed done. Hopefully I get all the residual air out and I won't have to pump the pedal. I can get it stopped with one pump now, but it's soft. Pump it rapidly a few times and the pedal firms up. I'll look at the drum adjustment after I've bleed them again. Feels good today though. If I hadn't cleared the video before I thought, I could have posted one of me driving back into the driveway/garage. Little too quick to clean out the security camera. Next time.
Happy to hear the brakes are better. It sounds like you have them under control, so after the next bleed and adjust cycle it might be time to move on down the to do list. Sounds like your going to be cruising around soon, enjoy the ride. Gene
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