I have a 95 GMC (Silverado?) 3/4 ton, long bed, cab has a back seat, but only 2-doors. Has a bad brake fluid leak. The fluid appears to leak from a hose that goes from the driver's side rear drum forward and through parts of the frame (inside a grommet where it passes through metal. The hose is rubber, but seems to have metal beneath the rubber. This hose appears to END at a connector where a cable comes from the front of the truck. This hose is connected to the drum forward of the rear axle. There is also a steel brake line coming from lines on top of the differential. I can't figure out what this damaged line is, so that I can look for a replacement. It doesn't even appear to make any sense that there would be a line, or that it would carry fluid, since a wire cable also continues to the rear, probably for a mechanical connection.

 

The wire cable(s) are for your emergency brakes, so yes, they are mechanical.

You need to pinpoint down the exact steel line that is leaking brake fluid.

That is best done with some cardboard laid out near where the leak is coming from.