how to PM rear brakes on a '99 C3500?

[coachjpg]

Folks,

I've been looking for a thread to tell me how to properly disassemble and reassemble the rear drum brakes on my '99 C3500 dually. I've found threads without pictures that use vocabulary that I don't understand. If someone can point me to an illustrated thread on this, I'd appreciate it. Or, if folks are willing to talk me through the process, I'll take lots of pictures and document it here.

I've read lots of discussion about various axle configurations. I attached photos of my diff and hub, which I hope will clearly document which configuration I have.



Depending on which thread I believe, my next step should either be:

• Soak the drum/hub interface with penetrating oil and use hammers to break it loose and slide it off the hub. or
• Remove the peripheral and central bolts from the hub, remove some "clips", and remove the axle.

If the latter, I need more details. How does one properly remove the bolt-like thing in the center of the hub? Must I open the differential to free the far end of the axle? Where are the "clips" I hear mentioned?

I've ordered a set of service manuals, but if possible, I'd like to make progress on this while I wait for them to arrive.

Thanks in advance,
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[coachjpg]

So it seems I have the fully floating axle, which means I do have to pull the axle to pull the drums, but I do not have to open the differential in order to pull the axle. The bolts holding the axle cap in place took substantially more torque than the lug nuts did. I ordered a bigger torque wrench for reassembly. The one that served me for the past 30 years only goes to 100 ft-lbs.

Tomorrow, I'm off to get a socket to fit the large nut visible behind the axle cap. For reassembly, I understand I'll also need bearing grease, gear oil for the diff, and new seals. I'm hoping the parts guy will be able to provide what I need.

Is there a gasket that goes between the axle cap and the hub? I found what was either a badly deteriorated gasket, or old grease congealed into the shape of a gasket. I'm not sure which.

Should I see gear oil at this point? Some posts warn to use a drip pan to catch oil from the hub. Does the lack of gear oil here mean my diff is low?

Thanks,
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[just a number]

what your dealing with is a very common 14boltFF. there is a gasket between the axle flange(the 8 small bolts) and the drum. most just use RTV to seal it. you only need a thin layer to do it.
First thing is do one side at a time. just lift the side your working on. that will drain most of the diff fluid away. if you do it level you drain the diff level down to the bottom of the axle tubes. more fluid mean bigger mess and more to refill.

Pull the axle all the way out. careful the heavier than you'd think.

To remove the nut, you need to remove to ring(small screwdriver) and there's a key behind it.

I found a magnet the easiest way to get it out.

Then just unscrew the nut.

You may have to back off the pads but that just the usual starwheel inside. there is 2 slots in the backing plate right at the bottom. they might have rubber plugs or the factory metal cover plates.

The drums have 2 sets of bearings in them and the drums are around 50LBS a side. they'll just slide off beings and all.

The seal you want to change is in the back of the drum itself. it keeps the gear oil where it supposed to be as opposed to your bakes pads.

now clean and inspect everything. the ares where the seal rides on the shaft has to be smooth to seal well. the rest is just normal.

installing is just reversing the steps.

the nut should be torqued, backed of slightly and retorted.

as for the axle itself, it'll slide in and stop with 2" or so. your have to tip/wiggle it to get it past the inner bearing and to slide into the diff.

the rest is just bolting up and setting the shoes.

check diff level after your done. this is what may happen otherwise.
http://www.thetruckstop.us/forum/showthread.php?19914-the-FAIL-thread

Now as far a grease goes. a thin coat is all you'll need. the bearing are lubricated by the diff oil. since your didn't find any check the bearings. it'll only be a couple of ounces at most.

that's it. any questions just ask.

one more note. if you can't get the socket of the nut you can tap the with a screwdriver and a light touch. installing it the way is the same you just have to set if by feel. a little drag is all you want.

 

[coachjpg]

Well, I think I found the problem. I'm no expert mechanic, but I bet those parts sitting at the bottom of my drum really belong somewhere else. That explains the unhappy noises I was getting from this wheel. I'm glad I didn't try to drive it to a mechanic.


See the nice, new parking brake cable I just paid $300 to have installed last week? I guess the mechanic forgot something when he installed it.


The bearings, drums, and shoes look OK to my untrained eye. I'm inclined to clean & lube everything, and replace all the springs and levers with a new kit. I also ordered a new seal, but I'm not sure where/how to install it. Do you guys see anything I'm missing? Should I replace the shoes? Does the drum need to be turned or replaced? Should I replace the cylinder while I'm in here? If so, what's the procedure for this?


For the record, my hub has only one nut. Other posts mention two nuts. Should this worry me? I used the needle-nosed pliers to remove the thin spring wound around the threads to retain the key, and then to remove the key. I used the punch to loosen and remove the nut. Very little force was required. I did not use a hammer, just tapped the punch with the pliers.

 

[just a number]

ok the seal is on the inside of the drum. it'll be level with the edge. as you probably noticed it has a metal outside, you just need to bend it a bit to get it out. the new one just presses into place(a small board and a hammer works nice)

the big ring is the only nut is there. the nut does come loose fairly easy. it's not a bad thing.

now as far a replacing parts. the drums are fine if they haven't been scored. you will need a new hardware kit, it's worth the price.I think I paid 20 bucks when I did it.

the shoes don't look bad. any glazing of metal bits in them? how think are they?

as far as the the cylinder goes gently lift the dust seal/boot and check for fluid. it it's dry leave it alone. if it's got fluid in there replace. it's leaking past the sealing ring??
not a hard job just unscrew the brake line and there's a bolt under it. that's it.

so far your progress is looking good. might want to check to see if your mechanic hooked up the bake cable

one piece of advice. watch the springs, their small but tough. if you get the holdown set(the one that goes through the middle of the shoe) the pin will fall out the back.

I thinks that's it for now.

 

[just a number]

Pirate4x4.Com - Extreme Four Wheel Drive

this will give you a whole pile of info for you rearend.you'll hear it referred to as the 14bolt bible alot.

 

[coachjpg]

I got the kits. They don't include the Brake Drum Bar. Mine got mangled:


Evidently this part rarely fails, so no one stocks it. It's a special order item, so I ordered one.

I also found a chunk missing from my aft shoe, so I got new shoes.

Before taking apart the brake, I sat with my new parts and looked at where they go. I wasn't getting it. Eventually I realized that I was struggling because they gave me the right-side self-adjusting kit for my left-side brake. I couldn't figure it out because some of my parts were the mirror image of what I needed. So I ordered the left-side kit.

I hosed down the cylinder with brake cleaner several times. I'm not making a dent in the crud. I'm not sure I can pull back the seals without getting crud in there. Is that a concern?

Once I have the right parts, I think I can get this put together, as long as I don't have to bleed the brakes.

Thanks for all your help.
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[just a number]

there are 2 seals for the cylinder. the outside one is just the dust boot. the one on the inside on is the actual cylinder seal. If you can get the boot to move don't worry about it.

the only spot the really needs to be clean is where the shoes ride on the drum. dirt=less friction=longer brake distance.

the only time you'll need to bleed the brake is if you open the fluid half up. your not, so don't worry about it.

 

[coachjpg]

OK. I now have all the parts & materials, but I'm still waiting on my Service Manual. I can see where most of the parts go, based on looking at the existing hub. I laid them out in rough position in the photo below.

But I have several parts left over, shown below the shoes in the photo above. I don't see where they go. I hate it when that happens. The photographs below show the left-over parts in detail. My Chilton manual isn't helping me with this. Can you folks help?


The Chilton manual makes reference to nails and hold-down springs, and I've seen reference to the "Jesus Clip", but the details are not clear. When it comes to brakes, I'd like more confidence that I know how to do this correctly.

Thanks again,
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[coachjpg]

I think I made some progress figuring this out, based on some exploded diagrams and on poking around the parts remaining on my truck. Unfortunately, I still have a few new parts left over. I bought the "all in one" kit plus the "self-adjuster" kit, and I think they each included an SA Arm pivot and a "Jesus Clip", so I think I have extras of those 2 parts. The remaining mystery part is the little black T-shaped metal part that appears below the shoes in the photo below. Where does that go?




I'd also like to verify some assumptions:

1. The shoes differ fore and aft, but not left to right. So the left and right forward shoes are interchangeable, and the left and right after shoes are interchangeable. Is this correct?
2. The 2 hold-back springs differ. One has a slightly tapered end that seems to fit better into the SA pivot, so I put it there. Is this correct?
3. Am I right that the SA pivot and clip are duplicates? Or do they go somewhere I'm missing?

Does the rest of the assembly in this photo look correct?

Thanks,
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[just a number]

how big are the "t" pieces? they almost look like covers for the backing plate. what's SA?
the space clip is for the e-brake arm. probably still on the truck.
so far it looks good.

 

[coachjpg]

Backing plate covers! That makes sense. They're about 1-1/2 by 5/16 inches.

SA = Self Adjusting. I saw the term used elsewhere, and I assumed it was common usage. Sorry to be obscure.

If you look under the blue spring in the photo, you can see a silver clip over the pivot pin hole. The pin and parking brake lever are still on the truck. They appear undamaged. The clip below the shoes is, I believe, an extra.

Does the rest of the photo look correct?

Thanks again for all your help.
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[just a number]

the rest looks good. make sure you hook the parking brake lever in first. you have to do so wiggling to get it on.

 

[coachjpg]

I removed all the old parts. When I took the plungers out of the sides of the cylinder, brake fluid came out one side. So it looks like I'm replacing the cylinder also. I'm worried about rusty fittings failing as I remove and re-install the brake lines. I really don't want to have to replace brake lines also.

I guess it's time I learned to bleed brakes. Any advice/guidance/references would be appreciated.

Thanks,
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[just a number]

spray, sit,spray sit,and spray some more. you just want to easy the lines off. don't force! all that'll do is round the nut. you oinly havew to disconnect the line at the cylinder itself. once the line is unscrewed the rest is easy. treat the line like an injector line, a big bend will break or kink it. little nudges are OK. it the line turns when you try to take it of your pretty much screwed. bleeding is easy. reassemble first them we'll talk you through bleeding.

 

[ak diesel driver]

heat helps sometimes

 

[just a number]

easy with the heat. propane will do just fine.

 

[coachjpg]

I think I'm screwed. The photo below shows the brake line, bolts, and presumably a bleed screw behind the cylinder, prior to my hosing them down with penetrating oil. I'll try spray, heat, and divine intervention to get these loose without breaking the line, but I'm not optimistic. I expect I'll need to replace the line, at least back to the differential.

The components at the differential seem reasonably healthy.

Below is the hub with all brake parts removed except the cylinder.

I presume I'll need to replace the rusted bleeder screw and brake fittings, assuming I can get them off. I'm hoping I can salvage the threads to which these things connect.

 

[just a number]

the bleeder screw just goes into the cylinder itself so no worry about those threads. you might get a nice surprise. I've taken off alot worse looking with much trouble.

just take your time.

 

[coachjpg]

OK. What's the best tool for this? I tried this on the fuel line with open-ended and flare wrenches, and all I did was round the corners of the fitting. I ended up replacing the fuel line with hose. Someone later told me the fitting was metric. I was using standard wrenches, not metric. There was so much rust that the standard seemed a better fit.

If you also happen to know the size of these fittings, that would be very helpful information.

Thanks again,
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