71 c20 brake lines

[ckincaid1404]

Ok, I've been a member for a while and been reading up and doing my research and I've decided it's finnaly time to start working on my truck. I have a 71 c20 long wheel base stepside that had been passed down in the family a few times and I was lucky enough to to receive it. I don't have a whole lot of money to spend on it right now so it's gonna be a slow build. Right now I just want to get her on the road and be able to cruise around in her from time to time. Right now the only hold up I have is brakes. I was wondering if anyone could help me out and might possibly have a diagram of all the brake lines and everything I need to get them replaced without having to take all of them off and match them up. Thanks for reading this and I look forward to reading much more. Thanks again
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[Yooper truck]

I just finished the brakes on my 71. Like you, I don't have a lot to spend on my truck and I am not a mechanic, but can handle small jobs.

One thing I would caution you before you jump into it is that if you have the original brake lines you may end up replacing more than you bargained for. Mine was a California truck up until 2009 with almost no rust and has not seen rain since. I was going to put in a Power brake booster and ended up doing a complete brake job replacing lines from front to back. The brass connectors on the old lines did not want to free up which ruined one line and it snowballed from there. I hope you have better luck than I did. On the bright side, I doubt I will ever have to do the brakes on my truck again.

[jocko]

Your best bet for brake line diagrams is the factory manual or LMC's catalog http://www.lmctruck.com/icatalog/cb/...rchTerms=brake lines

Keep in mind that for a 71 C20, you'd have 3/16" front brake lines and 1/4" rear brake lines. Also note that for a C20, the line coming off the FRONT of the master cylinder goes to the distrib block and then the REAR brakes while the line coming off the REAR of the master cylinder goes to the distrib block and then the front brakes. This is the opposite of the 1/2 ton master cylinder. See pic below. Concur with the above statement - it will always cost more than you think and you'll always find something you didn't think you'd find.

Do you plan to buy bearings and replace while things are apart? Make sure you know what kind of rear end you have before you order pre-bent lines (Dana 60 or HO52 are the possibilities).

The BEST advice I can give is take LOTS of digital pics as you disassemble and always leave one side assembled completely (except for removing the drum) so that, if all else fails, you can reference one complete functional side when reassembling the other side that sat dormant for a week while you chase parts you didn't know you even needed!

Also attached are a few pics of my 71 C20 brake rebuild for reference (D60 rear). Have fun!

[jocko]

more (note all rear brake pics are of the driver's side) - and don't forget to grease the little sliding pads on the backing plate so the shoes slide more easily.

[jocko]

1 - brake adjuster lever orientation
2 - front 3/4 ton disk assembly (not much to show on the disks, so this is the only one...)
3 - parking brake cable slip fit attachment
4 - parking brake upper aft pivot point detail
That's all I've got. Do replace the rubber hoses too! Good luck.

[JustinGJ]

Great thread, this is on my short list of things to do to my '71 C20. Stoked to see that the drums slide off of the hubs on the D60, I didn't know any of the older floaters did.

[jocko]

Just don't forget to remove the 2 big screws before you beat it with a big ol hammer

[Cape Codder]

The easiest way to replace brake lines is to remove what is left of the originals and use them for patterns to make new lines. Tubing benders are cheap and as far as flaring lines you have two options. You can buy preflared sections of line and put them together with couplers. The trouble with this is you usually have extra line as the sections don't usually come out to the right length. Or you can buy tubing in a 25' roll and buy flare nuts as needed and make your lines as needed. You will need to learn how to do a double flare and need a flare tool. You don't need an expensive flare tool the basic ones work fine but require a little more effort. You tube has many vids to flare and replace brake lines. Tubing wrenches will do a better job of tightening flarenuts as an open end just rounds them off. To remove old tubing from wheel cylinders it is easier to cut the line near the nut and put a socket on it to loosen it. Penetrating oil will help.

[ckincaid1404]

Thanks for all the help and info. I'll for sure look into all that. I'm going to go through all the lines and replace them, the truck has sat for 16 years but amazingly runs perfect after a few small fixes. I will be replacing all brake components on it.
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[davem815]

I'm replacing brake lines on my '70 3/4 ton now. I blow a rubber hose, but I'm replacing all the lines too.
I used a couple rounds of penetrating oil, let them sit a few day, then using a flare wrench I was able to get most of them free by tightening a little first, then lossening. A couple were rusted to the line and twisted the lines off, but I had already ordered pre bent lines, so I didn't care. I have not got the new lines installed, so I can't comment on fit yet.

[ckincaid1404]

I'm having trouble finding the front brake hoses for my truck. Any year but the 71 seems to be available at local parts houses but no one lists it for the 71. I suppose ill have to take mine and get them made.
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[72 K20]

CKincaid 1404
Classic parts carries the front brake hoses for 71-72 C20,, I'm going to order from them.
Stay away from the ones on Ebay from inline tube out of Michigan,, they sell under the name motorcitymusclecar.
http://www.ebay.com/itm/200919964483...S:1123&vxp=mtr
I bought a set,, the price was right, fast shipping ,,,,,,,,,, both hoses were right at an inch short. Now have to go through the hassle of returning them .

[808turbo]

Jocko,

Did you make your own lines from MC to distribution valve? Do you know what size thread the MC side is? And if you did make them where did you get the those tube nuts from?

Thanks

[rx78nt1alex]

I'm upgrading my C10 to C20 brake booster for that added power. Here is a post I posted some info on doing the C20 brake lines.
http://67-72chevytrucks.com/vboard/s...06#post7147206

[808turbo]

RX,

Thanks, I wasn't sure on the male thread sizes, I hate when they put these larger tube nuts on the MC and proportional valve.