1986 GMC C3500 Frame Brake line fitting

[TSmith1941]

I've done a very very quick search for other posts but didn't see exactly what I was looking for, if I missed it please feel free to redirect me.


I'm redoing a 1986 GMC C3500 Dually and am in the process of replacing brake lines. I live in the rust belt (Upstate NY) and hit a point where I want to pull out a grinder.

I bought a new rubber hose to run to the front driver side caliper, but can't seem to get the one that goes through the frame. I don't want to booger it up until I know I can get the part or can find a similar part. I've sprayed it with fluid film and PB blaster and rounded off what was left of a nut.


I appreciate any info!

- Tommy

 

[Bennyt]

If you aren't using a flare nut wrench, make sure you do going forward. I assume you are referring to the little nut that threads into the end of the hose. I would try a little heat. You can always cut off a couple inches and flare and replace the line or a local Tube and Hose shop should be able to replicate the entire section of line/ tube fairly cheap. I was quoted $250-350 parts and labor last week to replace all the metal tubing for brakes and fuel lines front to back which is cheaper than I can buy lines for at the store. I've had little sections fabbed up for $15-25 in the past that I didn't want to deal with trying to bend and flare myself.

I guess what I am trying to say is that lines are cheap and readily available so do what you got to do to get it done. Even if you have to buy a $10 bender and $10 line and do it yourself.

 

[TSmith1941]

I have an assortment of flare nut wrenches, but this one was shot from the getgo. I'm talking about the piece that screws into a connector that crosses through frame. Picture attached is the part

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[Jethro224]

The threaded end of the brake hose should go thru the frame. There's either a nut or a clip that holds it in place on the inside of the frame.
Sounds like you have a brake line nut that's froze in and rounded off.
Since you're replacing the hose anyway you should either replace the brake line now or at least cut it, replace the nut and re-flare the end.

 

[bucket]

The brake line can just be replaced with regular parts store stuff. You have to bend it yourself, but standard 3/16" line has the right size thread on the tube nuts.

 

[Subourbon]

The brake line can just be replaced with regular parts store stuff. You have to bend it yourself, but standard 3/16" line has the right size thread on the tube nuts.

I'm doing the same thing but in the rear. Was doing .y drums and my brake line snapped off, so got the flared and readied with fittings straight line stock napa like you mentioned.

Thing is, I brought my wheel cylinder in to test my fittings, seemed to fit, bent my line, and it wont thread into the brass hydraulic box on the end of the rear center brake hose (name for it?lol). But I got the old brake like fitting off with a 3/8" wrench, but the new ones are only working with a 10mm.

But if it fit in the wheel cylinder, shouldnt it fit on the end of brake hose box?!?!?

 

[bucket]

Yes, the outlets on the brake hose should be the same thread and pitch as the wheel cylinders. I've never run across a universal replacement line that takes a 10mm wrench though?