I started shooting brake fluid out from the back. Took it to the shop and they said that the Lines are rusted and the part that they go into is rusted away. They stated that they can’t get the parts but can’t tell me the name of the part. Looking at a Moper diagram it looks like it could be the “Brake Line Union” I have looked for the parts on Mopar (discontinued) Auto Zone and Advanced Auto (Not Listed) I tried the Car-Parts.com (nothing). Where else can I look?

Does anybody have a idea what part or parts it could be?

 

There is a junction block down on the axle itself, that splits flow to each wheel..... Worst case, just get a T union, run the lines to/from that, and zip strip it to the axle....

 

I had to redo all the hydraulic lines on my '97. I ran into problems with some fittings and junctions are metric and others are SAE. I ended up replacing all the hard lines to the rear, using adapter fittings to get everything hooked together. You have a junction on the differential attached the RWAL ABS sensor. Take your old lines to the parts store, I went to Autozone because they were close, and mix and match what you need. Even if they aren't leaking, replace the lines to the rear wheel cylinders. If they aren't broke now, they will be when you start working on them. I didn't replace the steel lines from the master cylinder to the junction, but all the others were replaced. It was a northern truck and the tin worms had been busy.

 

as grouch said, your only option is literally cobbling stuff together. Also, you can't get to the rear brake line mid-frame because it goes behind the fuel tank...which means you have to drop the fuel tank, and if your brake lines are rusted, you don't want to know what's holding up your fuel tank (probably nothing).

Best option is to get a roll of the green nickel-coated brake line tubing, straighten it out, and run it along the frame next to the existing line and then slip it up into the frame around the fuel tank. Most of the fittings will be M10x1.0 or M12x1.0 Bubble Flare except a couple, as grouch mentioned, could be SAE inverted flare. But then it will go back to metric bubble flare.

 

This brake line seems to have a Union on it and has some type of junction on it. But I'm guessing because you don't know exactly which part you need and you haven't even posted the year of your truck. They have variations... 03-04 had rear disc, vs earlier years.

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