2nd Gen Non-Engine/Transmission Brake Failure

[TSielski]

On the way to work yesterday the brake pedal suddenly went to the floor, luckily while rolling to a stop slowly. To make a long story short, after nursing the beast home with the emergency brake, found the rear axle covered with brake fluid. Closer examination last night after work revealed that the steel brake line to the rear axle ruptured at a 'convenient' point where the line runs between the fuel tank and the frame!



Although I hope to give the mess a closer look tonight, does anyone know if this steel line has a coupling anywhere on it's length, or is it one piece from its end point just behind the fuel tank all the way to the master cylinder? It also looks to me that the fuel tank will have to be lowered to gain access, which is absolutely lovely as I just filled up on the way to work. I've lowered the tank once nearly empty, but not with virtually 34 gallons of diesel!



A last question if anyone knows, is this a standard 1/4", or 3/16" brake line, with SAE fittings, or has DC used some 'yakimoto' specials available only thru them?

Appreciate anyone's insights.



Tim

 

[dremelts]

Wow - glad you didn't crash. Did it rust or was something rubbing against it? -let us know what you find.



I thought that with a split braking system that you shouldn't lose your brakes entirely if one of the lines broke.

 

[Joseph Donnelly]

As Dave pointed out, the front brakes should have still worked. Check the master cylinder and proportioning valve. To fix the rear line, either cut it in front of and behind the tank and put on double lap flares, put in a new piece that you can just slide up in there and where it passes a hole through the frame rail, pull it tight with wire or zip ties to the frame so it won't vibrate. You can buy pre-made lengths of line (up to about 5' long) and brass couplers at parts houses. Best would probably be to replace the entire length of that line with either pre-made lengths coupled together, or a custom length that you put double lap flares onto.

 

[Rman]

The tubing is cheap and I generally make my own lines if the run is relatively easy without too many bends. I have a bender but some of the stock bends are difficult to make happen. Obviously pick out which option is best, but i bet the line won't be cheap from DC.



I agree with above, the front brakes should have worked if you only lost the last half of brake fluid, check that proportioning valve.

 

[TSielski]

Appreciate the replies!.

Dave was right, after a fashion. The front brakes did generate some stopping force, but not anything confidence inspiring. The pedal went to approx 2" from the floor, and the truck would not roll once stopped with the pedal applied, but trying to stop while moving required an awful lot of effort, and that was from no more than from 5 or so mph.



I've already come to the conclusion that making either a replacement piece of tubing, or trying to bend up an approximate total replacement, rerouted somewhat, will be the plan. Just for grins, I spoke with three local dealers and one independent repair shop, none of which could (or would) drain a full diesel fuel tank since they all wanted to lower the tank.

First major task is to determine the size of the line. Then it's game-time. Nice project with the seasons first significant snow predicted for this weekend!



Tim