The Stovebolt Site Forums The Shop Area General Truck Talk HELP, ADVICE NEEDED 3/4 TON BRAKES

Well I got myself a really bad wheel cylinder leak, I found this out when my foot went clean to the floor while trying to stop my 3/4 ton 49 chevy like Fred Flintstone. Anyways, I've been every where and nobody will touch this rear brake job, cause they say it's too hard to do. Something about the 3/4 ton axel. So I need advice to do it myself. I can buy wheel cylinders for the rear for about $50.00 a pop, or rebuild kits for about $10.00 a pop. Is rebuilding the rear cylinders that hard, or should I just replace the wheel cylinder? And do I need special tools?

Thanks in advance,
Sam

Man, for $50 a pop, i'd go with the off the shelf cylinders.. that way the job is all done for you.. then, just for fun, try and rebuild your old ones.

You dont really need any special tools just lay out the parts as you take them out and replace in reverse order.the bearing retainig nuts will be the hard part if you dont have a socket that big.You can use a hammer and punch to remove/replace them just dont over tighten and smear some grease on them when you reassemble so they wont be dry till they pick up lube from the rear end.also if you have a camera take some pics before you disassemble it then you have a reference when you go back together.

The reason they don't want to do it is the full-floating axle, which isn't that difficult. For instructions, either look in your factory shop manual.

The biggest issue is installing the drum and hub without damaging the oil seal, it needs to go straight on so the seal isn't nicked. I usually use a floor jack to support the drum.

I would suggest you buy the new wheel cylinders. The old ones can be honed, but usually there is enough pitting that the old ones will need to be sleeved to use again.

Also, replace the springs. They are over 50 years old and are prone to breaking. New rubber hoses and oil seals.

Another problem can be the drums. The only replacements are used, you can't buy new. Be sure to get your's turned. There are no tricks to turning these old drums, but the machinist does need to know they aren't made new.

Also, take a picture of the brake after you remove the drum, it will help with assembly. Another tip is to only disassemble one side at a time, gives you a reference to check when you put things back together.

One of the tricky parts will be adjusting the E brake cam. You should definitely have the factory manual for this. The springs may be hard to come by, maybe Jim Carter would have them. There are retainer clips on the pins that hold the shoe assembly together. These are difficult to find new so if you can save them, that would be a good thing. Some of us believe that a C-clip of the proper size would do. Also if your E Brake cables are seized, you will need to free them. There are ways of doing this.

I don't understand the comment about the hub seals. The drums should come off with the hubs in place.

i just went through the rear brakes on my 50. as stated previously, the 3/4 ton brakes drums are hard to come by.

i would also recommend buying the new wheel cylinders and keeping the old ones as a rebuild backup.

just curious to know, if a person was not interested in keeping the rear brakes totally original on a 50, would it be possible to swap out the carriers, brake pads and drums to a 53 or later set-up? when i was having trouble finding drums for the 50 set-up i had started investigating this scenario, but abandonded it when i stumbled across some old drums. from what i could tell the only difference was in the width of the later style vs. the earlier style.

Thanks for the advice everyone, I'm gonna attempt to do this on Monday, that way if I need parts, it's not the weekend and hopefully I can find what I need.

Should I do a crappy job and I find this out during my test drive the hospitals are less full on Mondays!

Thanks again,
Sam

Let me know how it went. I have to do my 47 3/4 ton as soon as the parts come in.

Fred, the pre 50 Huck rear brake drums are separate from the hubs, so the bearings don't need to come off. Once the large flathead screws between the lugs are off, the drum soud slide off. Loosen off the cylinder first, then to get the shoes off, undo the park brake cable at the crossmember at the front of the box. The cylinder ends may pop out when the shoes are removed. Have a clamp or piece of bent rod handy to secure the cylinders. If you are just changing the cylinders, you don't need to remove the shoes totally, just unhook the return spring and the shoes will separate.

Good luck

It's easy. Go for it. Those mechanics that wouldn't do the job suck.

You can rebuild your cylinders IF they aren't excessively pitted with rust.

Hey everybody, sorry it took so long to post the results of my brake job but it took longer for the parts to get to me than even they thought.

Well four bloody knuckles, 1 two inch gash(sledgehammer, don't ask) and I don't know how many impure thoughts of sending my truck to Iraq to search for street mines if it didn't get with the program and walla, I did it, and the ole girl is stopping better than ever. Oh and on my 49 3/4 ton the drums are separate from the hubs.

The best advice is to do just one side at a time while using the other side as a reference, and I also took pics to reference also.

Thanks for the advice everyone.