Rear brake bleeders

[JerryIndy2112]

My truck is a 1971 GMC C3500. One of my rear hard brake lines ruptured. Ordered a set of hard brake lines for heavy duty truck axle. Parts came and match what I have. Crawled under truck and started getting busy. Then I found the real bummer here. One bleeder will not break free, the other is broke off. I have soaked them with WD40 for 24 hrs and bought a screw extractor set. But this thing is seized bad. Any tips or hints for getting these out and replacing them?

[RodnRudy]

You'll probably just have to replace the wheel cylinders on the rear backing plates.

[Willie Makeit]

new/rebuilt ACDelco wheel cylinders are like $7 each from Rock Auto

[JerryIndy2112]

Thanks for the replys

[JerryIndy2112]

Ok, I got the one out. I would love to redo all the rear brakes. I am having trouble finding a diagram of the 1 ton truck brake and axle to see how this all comes apart. The 8 lug full floating axle is very different than the 1/2 and 3/4 ton axles and drum setup. Can anyone post a link to what is relevant to my setup? Not going to be able to do this today. I am hoping to make some progress though.

[BigBird05]

I have more luck using PB Blaster that WD 40. I have soaked some thing up to a week to get them to come free.

[JerryIndy2112]

Ok. So I was unable to remove the broken bleed. So I am working on replacing cylinders and shoes. Went to pull drums, axle came out easy. Tried to take off drum, no go. There is a large bolt on top of inner assembly. Is this what is stopping the drum? Here is what I have.

[JerryIndy2112]

This is the back

[AussieinNC]

rear brake shoes are adjusted out and causing the brake shoes to hang up on a worn edge inside the brake drum....

Look at the bottom of the backing plate for a slot,,,,it allows access to the brake adjuster ....using a short screwdriver or a brake adjuster tool, back off the notched adjuster...if you turn it the wrong way the brakes will expand tighter on the drum...just go the other way....

Adjusters are available if they are torn up...

[Jason Banks]

Use some heat. I like a propane torch, the kind you would solder a copper pipe with.

[JerryIndy2112]

Thank you Aussie, you were correct. loosened the adjuster and drum came off. I have ordered cylinders for the HO72 axle and got the right ones. They are an exact match. Now I am trying to order the shoes. Shoe ordering is being kind of a pain. Drum is 15" by 4", actual shoes in place are 13" and are 2.5"
When I go to order shoes they list the 15X4 or the 13X2.5. Do you order for whole drum size or actual shoe size. I hate waiting on parts only to pull them out and they are wrong. Does anyone know how these are ordered?

Thanks, Jerry

[toolboxchev]

It is wise to replace all the springs and hardware including adjusters and most important the arms that actuate them.

Been there, I was happy I did the first time.

[JerryIndy2112]

Yes Toolbox,
While I am in there I would like to put it all up to new. I have already done the rotors and calipers on the front. I would have liked to have done it after I got some other projects done, but broken line, broken bleeder. So now is when I have to solve this. My problem is that parts are listed in 2 sizes. The 15" kits are not available. the 13" are. Wondering why they are labeled that way in the parts list. I am unsure of what I can get, if it will fit. One of the frustrations of having a nearly 50 year old machine. Yes she is pretty, but damn it is hard to find parts at times. If it were the 1/2 ton, I can get most anything. But being she is the one ton, many parts are just not made anymore.

Jerry

[AussieinNC]

Rock Auto lists 13 x 2 1/2

https://www.rockauto.com/en/catalog/...rake+shoe,1688

If you then scroll down the RockAuto listing you will find Adjuster Repair kit....

Measure the original shoes....they should be 13 x 2 1/2.....

Where are you measuring the 15 x 4 ?

Check the radius of the original shoes to the inside surface of the drum...13 " shoes will have a different radius to 15"....

[randy500]

Always order by shoe size.

[AussieinNC]

Originally Posted by randy500

Always order by shoe size.

YEP !!!!

I dont ever remember seeing 15 x 4 shoes....

13 x 2 1/2 is usual size...I have a set on my stock shelf...

[JerryIndy2112]

thanks for the information, I measured the 15X4 by the actual drum size. The actual shoe size is different, 13X2.5. I was just worried how they measured the actual size. I see both in lists of parts. I have looked on several sites searching for the right parts. The HO72 rear axle and such have given me frustration. I am told the drums are not made anymore. I just hate ordering parts that are wrong. The cylinders I ordered were for the 7200 lbs axle, but there is a listing for an 11000 lb axle. this is a one ton special camper bought in 1971 in California with a dealer installed camper on it. So some of the setup is "special".

Jerry

[JerryIndy2112]

Ok, I got my cylenders, shoes, adjusters. Got passanger side drum off today. I already had drives side pulled. Passengers side has deep grooves in it. Very deep. Took them to get them turned, or to see if it is possible. The place cannot get the specs, it is too big to fit on there machine, and off course I need to take out bearings and seals. Bearings and seals are actually in good condition.
My searches say that I cannot get those drums, no one makes them. The axle is the HO72. Anyone know of a source? I would be happy to buy a set used as long as they are turnable. The dream situation would be to find an axle that had all this done before it was retired. I don't really know where to go from here. It sets in the driveway on stands, axles pulled and drums off. I looked into disc conversion. Looks very involved for me.
Thanks for any ideas provided.
Jerry