Leaking brake fluid

First you need to identify what is leaking. The best suspect is a rusted steel line between the axle's center section, and the wheel cylinder. An equally-good suspect is the steel line running from front to rear, along the left frame rail. Next would be a leaking wheel cylinder, although those do not normally leak real fast.

Other potential suspects include the rubber flex hose right above the center of the axle, and the height-sensing proportioning valve, if your truck uses one. Once you figure out what is leaking, we will discuss the best plan of attack. If you are not sure, try to post a photo of where you see brake fluid leaking out.

Include whether your truck has no anti-lock brakes, rear-wheel anti-lock brakes, (RWAL), or four-wheel anti-lock brakes.