Rear brake drum stuck...ticking!

[nosajwp]

For a while now, I've been having the ticking/thumping from the rear that occurs at slow speed when I'm decelerating. I think my rear brakes may need adjusting or machining, so I was going to check them out this evening, and my drivers side drum is stuck to the drive flange on the shaft. Any idea why, and how I could get it off? It turns, it just won't come off!

[Matthew Currie]

For a while now, I've been having the ticking/thumping from the rear that occurs at slow speed when I'm decelerating. I think my rear brakes may need adjusting or machining, so I was going to check them out this evening, and my drivers side drum is stuck to the drive flange on the shaft. Any idea why, and how I could get it off? It turns, it just won't come off!

Rust. If your Jeep is recent enough to have a C-clip rear end (sometime around 89-90 I think) there's probably a good bit of end play in the axle. One possibility is to try pulling the drum/axle out as far as the end play allows, and lock the brake. Then hit the axle end with a BFH . You shouldn't have to hit too hard, but it might crack the drum loose from the hub. Once the rust bond is broken at all it should come free. If you have a lot of miles on the drum, there may be a ridge on it, and you'll still have to back off the adjuster even though it's a little slack.

[Eagle]

If it's loose but won't come off, it isn't stuck on the drive flange. The shoes don't extend all the way to the absolute edge of the wearing surface of the drums, so after many thousands of miles a ridge of rust, crud and brake dust builds up. To get the drum off you probably need to unadjust the shoes with the star wheel to retract the shoes far enough that the drums can slide that ridge past the shoes.

[8Mud]

Something to keep in mind, the adjuster on the left screws in, to the right/to loosen the shoes (as your looking towards the front of the XJ, like a normal nut or bolt), so you can adjust the shoes in, to clear the ridge on the inside of the drums. The star wheel on the right side is reverse thread.
I clean up trhe hub some with a wire brush, squirt a little oil onto the hub and tap (with feeling) the back of the drum with a hammer, at different points, to help keep the drum from jamming on the hub.
I´ve beaten a lot of drims off with a hammer, but did crack one doing that. A lite coating of lithium grease on the hub center, makes taking it off next time much easier.

[Matthew Currie]

If it's loose but won't come off, it isn't stuck on the drive flange. The shoes don't extend all the way to the absolute edge of the wearing surface of the drums, so after many thousands of miles a ridge of rust, crud and brake dust builds up. To get the drum off you probably need to unadjust the shoes with the star wheel to retract the shoes far enough that the drums can slide that ridge past the shoes.

I'm assuming that when he says it turns but won't come off, he means it isn't loose at all.

Now here's a question: why don't the shoes go all the way to the edge? I know they never do, but I'm having trouble figuring out why they couldn't.

[8Mud]

I'm assuming that when he says it turns but won't come off, he means it isn't loose at all.

Now here's a question: why don't the shoes go all the way to the edge? I know they never do, but I'm having trouble figuring out why they couldn't.
I´m just guessing, in school they mentioned something about allowing some extra drum for end play at the axle shafts and something about side play in the shoes. There is probably more than one reason. If you´ve ever noticed when power sanding on a flat piece of metal, the edges are the first part to glow. Thinking maybe the extra material at the edges, is there to help deal with the heat.

[8Mud]

I'm assuming that when he says it turns but won't come off, he means it isn't loose at all.

Now here's a question: why don't the shoes go all the way to the edge? I know they never do, but I'm having trouble figuring out why they couldn't.

Finally came back to me, a wonder since I had the school in the late 60´s. The shoes don´t sit exactly 90% to the axle. They are designed with a little toe in, which forces the shoes into the backing plate ( a little during braking) and forces the axle and drum out a bit. Supposed to reduce chatter and binding. The way the instructor explained it was, that the shoes screwed towards the backing plate some, during braking.

[Matthew Currie]

Finally came back to me, a wonder since I had the school in the late 60´s. The shoes don´t sit exactly 90% to the axle. They are designed with a little toe in, which forces the shoes into the backing plate ( a little during braking) and forces the axle and drum out a bit. Supposed to reduce chatter and binding. The way the instructor explained it was, that the shoes screwed towards the backing plate some, during braking.

Makes sense, I guess. I also started thinking about the cross-section of drum, shoe, backing plate, etc. and the way the drum is grooved on the back to form a seal with the backing plate. That means that the innermost edge of the drum is thinner than the rest, so the heat explanation in your prior post also starts to make sense. When you think about it it's a wonder drum brakes work at all. I remember long ago hearing the BMW boxer motorcycle described as "the triumph of development over design." That could apply to drum brakes too, I think.

[gjxj]

If they are stuck on the hub, which they probably always are.. what you need
is heat. Take a propane torch to the drum near the hub. On mine after
maybe 2 minutes you'd hear a pop and they come loose. I'd guess if they are rusted bad you'd also need to use a hammer. After its loose on the hub, then start messing aound loosening the shoes.

[dizzymac]

BFH........that would be Big "Furry" Hammer...right

[bustednutz]

I used Heat on my old car to get the drums off. Works every time. And not just for drums. I heat all stuck bolts as well. Just apply it like he said to the center of the hub and move it in a circular motion around the lug studs some too. Then hit it with a hammer. It will pop right off.