Monday 11 June 2018

Rear Drum Brake Replacement

Every ten years or so, I need to rebuild a set of drum brakes. It serves a reminder of just how much I dislike them. They aren't hard, they aren't really complex, there are just so many bloody springs and finicky parts. 

When it comes to drum brakes, always, and I mean always, order the new hardware kit. I ultimately went with Wagner 9" brake shoes and the Carlson Rear Drum Hardware Kit. The Carlson kit was a spectacularly complete kit. Nothing had to be reused from the original hardware.
Good thing at that, considering the innards of the brakes were pretty much rusted solid and not really doing anything anymore. 
You may notice that I'm working with a jack, and a tire under the control arm as a safety device. Don't do this, it's not safe, you will die. I haven't yet, but my tire has caught my Jeep once when my Hi-Lift fell over in an emergency situation. In any case, yeah, use jack stands. 

Get the Jeep up in the air, get the tire off, and pull the drum. If you're lucky, the drum will slide right off because the brakes are shot and not working. If you're unlucky, you'll need patience, heat, choice words, and a hammer. I was lucky, my brakes were shot. 

Once the drum is off, I suggest taking a picture or two. There are a bunch of springs, levers, a cable, and an adjuster wheel. Having the pictures will help with reassembly, if you do need a reminder, just check the other side. This is why you only do one side at a time. 

These steps are not any official steps, just the way I do drums. 

Start by removing the two top springs, using a brake spring tool helps. Well worth the investment. Next remove the retainer springs. These are the round disks, just passed the halfway point down on the shoes. To remove them, put a finger on the pin behind the brakes, using pliers, push the disk in and twist to release it. Much easier than it sounds on rusty springs.
Finally, pull the shoes apart, and remove them from the backing plate. 

At this point, it's worth sitting the old set next to the new set and making sure you get the proper shoes for each side. 

Using the new hardware kit assemble the adjustment lever and spring. Apply some axle or chassis grease to the inside of the adjuster to keep it from seizing up. One point to be certain on, make sure you're using the proper adjuster. They are left and right side specific. 

Once you have the bench work done, it's time time to install the shoes.
Start with ensuring the parking brake plate is slotted in correctly (it'll be the thing that didn't come off with the shoes, and is on a cable). Next move to the retainer springs. They will cause you to use some adult language. Once done, slide in the adjuster, and the shoe to shoe spring over it. Next, I slide in the above axle cross bar, finishing with routing the adjuster cable, and top springs. (These are not official names, just saying) 

When done, slide the drum on. It should be lose. Take the drum off, and adjust the adjuster a bit and test the drum again. Keep doing that until you get a slightly snug fit. Put the tire on, and you're done.

These are meant to be some simple steps, and after following them, you too will understand why auto manufactures are moving to discs. Technically speaking, drums do provide much more stopping power. They're "self energizing", meaning that the force of the drum against the shoes, force them to grab harder (like a wedge under a door). They don't do as well with water and debris, and as you can see from reading this, a pain to work on. 

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