it can go dry, i just did a astrovan yesterday where they blew a front and rear line and the master went completely dry. dont hundreds of vehicles where the entire system went dry and never had one problem but some people say they have. one thing you can do is if your master hasnt went dry, fill it up and leave the cap on it and it will usually cause like a vapor lock after enough fluid has come out and stop all the fluid from leaking but not always the case.

i usually just try to be quick and rip the line out and replace it before it all leaks out.

 

I'm gonna say replace the lines and worry about the abs after if you need to do anything with it, not worth mucking around trying to do it without draining it.

 

That's sounds a lot easier to drain the system, replace the line, refill, and bleed. Now I have to get the time to fix this thing.

 

How did it go?

I just blew the line going to my rear brakes (98 4dr 4x4). Mine blew right near the tranny crossover rail.

It looks like there is some kind of factory "union" or connecting block, towards the front of the frame rail just before the line goes up to the ABS unit.

Anyone know of a diagram showing the brake line routing and individual brake line pieces and line sizes?

Thanks.

 

I haven't seen a diagram. It's pretty straight forward.
Go to an auto parts store and pick up a 1/4" inverted flare plug, our part number is a PL141-4.
There should be a join in the rear brake line somewhere within a few feet of the ABS module(mine was toward the back rear of the drivers side front wheel well) that you can disconnect the rear line and plug it with the PL141-4. From there you can remove the rest of the line all the way back to the rear flex hose and make a replacement using it as a template for all the bends.

If you pull the whole line out toward the rear of the vehicle it comes out fairly easy.

 

I did more digging, found this diagram. The site has more but the site is a bit awkward to use IMNSHO.

T BRAKE LINES/REAR (LF6/4.3X,L35/4.3W)

 

That's good if your going to order one, and the bends look right. It's actually around 11' long though.

 

Buying one pre-bent doesn't seem to exist anywhere.

Probably less than 11 feet though. Straight line from the front connection at front wheel well to the rear axle is just 8 feet. Add some bends and turns, maybe 18 more inches. I am about to find out.

 

My Update:

Replaced the main line from rear brakes to firewall. Used 3 pieces of 1/4 inch pre-flared pipe. A 12 inch piece from above the rear axle connection with the flex line. Brought it up and over and then a short bend parallel with the frame. From there a 30 inch piece along the frame to below the rear door. After that a 72 inch piece to connect forward to just below the firewall, behind the front wheel. That makes 9 1/2 feet of brake pipe.

I used all of the factory clips on the frame except the one at the rear axle - the coupler wound up right there.

I also decided to replace the pipe that goes from the ABS unit down to the frame. That required a 40 inch piece while duplicating all the turns and "spring" coils of the factory piece. Had to cut off the smaller flare nut and use the factory larger nut that goes into the ABS unit.

Here is a side by side view of the ABS pipe. Got too dark to get pics of the main line. Sorry for the crappy cellphone pic.



PITA & took a long time. This one goes from ABS unit down to the frame just below the firewall. Crowded area. You can see the crusty rot on the old piece at the bottom end (right side of picture).

.

 

Well done! Looks factory.