1999 F350 Brake Problems

A friend of mine has an 1999 F350 Powerstroke, yesterday he applied the brake to come to a quick stop, the truck started to slow down and while holding the brake pedal, the bakes were released (there was no braking at all), then a little more braking followed by a total release of the brakes again. He almost got into an accident. The same happened to his wife about 6 month ago and she ended up hitting a car in front of her. Back then they took the truck to the shop where nothing faulty was found!? No ABS light or any other warnig lights came on.
The brake pedal stays firm and doesn't sink to the floor.
Any ideas?

The first thing I'd do is check the brake fluid level. The next thing is to take off all four wheels and inspect the pads, rotors and callipers. He could have a leak some place in his brake lines causing this too.

If he's got a good amount of miles he may want to consider trying ceramic pads soon with either new callipers or a the calliper kit with new slides and hardware. More than likely it's calliper related if the brake lines and fluid is ok.

I would look into the vacuum pump unless his has the hydraulically assisted brakes that run off the power steering pump. Diesel engines do not generate enough vacuum to run power brakes. My 95 has a mechanical pump driven by the serpentine belt but I believe the 99 and up went to an electric pump, mounted in the right inner fender area if I am not mistaken (which I often am).

Dave / Believer45

Shooter,

There are two likely causes, the first is that the ABS system thought there was a need to intervene due to a sliding wheel. Given that sand, frost, snow, ice, etc can cause this especially on the REAR axle, that I what I would suspect.

However, as Dave pointed out, if the vehicle is equipped with the belt driven vacuum pump, OR hydraulically assisted brakes where there is a problem with the booster, pump, or steering gear that could cause the very same symptoms.

At any rate, given the fact that this HAS CAUSED an accident already, it is time to contact the folks at the "NTSB" to notify them of the problem. I would also call Ford's Consumer line, and with a copy of the dealer's invoice in hand notify Ford that the vehicle was brought in for this concern, and that the dealer found "no problem". Ford should also be told that the NTSB has been contacted.

Written LETTERS to the NTSB and Ford Motor Company WILL get a response.

The dealer said he installed new front rotors and pads and said that should take care of it. They took the truck for a test drive and it did it again, they were puzzled.
They than said that they turned the rear rotors and installed new pads and they couldn't repeat the problem and released the truck. On the invoice were no charges for new front rotors and pads (dealer said they took them back off since that didn't cure the problem!???). The front brakes only had 9000 miles on them.
I guess time will tell if this was the right fix because it took about 8 months before the first occurrence (accident) and the second one and then another week later was the 3rd (near miss).
He will contact the NTSB in regard to this.
Thanks.