I have a 1989 Ford F-350 7.3L Diesel 5spd front disc, rear drum (duals) that has around 130k miles on it. The problem I'm having is when I apply the brakes they stop the truck fine, but with continued pressure on the pedal it will very slowly travel to the floor. I was told the problem was the ABS unit (mounted to the inside of the frame, left side of the truck) so I replaced it (with a rebuild) but that didn't fix it. I replaced the master cylinder (a new unit from ford) and that didn't do it either. A friend of mine removed the hose from the booster and blocked it with his hand while I depressed the pedal and that seemed to hold, so I replaced booster but that didn't help either. I've been over the truck front to back and there are no leaks and the fluid level hasn't dropped in the resevoir throughout this adventure. The front pads and discs have a few thousand miles on them and the back shoes and drums are new. Assuming the parts I installed were good, I'm at a loss as to what the problem is, so any suggestions are greatly appreciated.
Wednesday, June 6th, 2007 AT 9:39 PM