Help diagnose brake problem.....please.

[trekker]

Have 91 7.3 IDI 4x4. Went into town today and when I stepped on the brake pedal it was hard as a rock and I had no brakes. PANIC CITY. Tried to pump the brakes and eventually slowed to pull over on the side of the road. Turned around and went back home.......very carefully. Brakes worked ok on the way home but it did the same thing when I pulled into my property. I am thinking it is a problem with the brake booster. Does that sound right? Any advice greatly appreciated.
THANKS IN ADVANCE.

[atvrider93]

the problem is most likely with the power part of your power brakes. whether the booster part has a leak or what I'm not sure.

[tsalinas]

I have '97 that had the same problem.It scares the hell out of you. My problem was that the vacuum pump went bad. Diesels don't create enough vacuum on their own enough to power your power brakes so they put in a vacuum pump to do that. It is located at the front of the engine on the drivers side along with the A/C compressor and all that stuff that is run by the belt. Just follow the line from the booster to it. Hope this helps.