I own a 2000 Peterbilt 330 series tri-axle dump truck. I normally work this truck everyday but due to slow work recently it isn't running nearly as much. Right now I'm working a job 140 miles away from home so I leave it on the job and commute back and forth. I started it up yesterday for the first time in about 2 weeks and let it warm up real good and then I put it in gear and proceeded forward. When I went to stop I had absolutely no brakes. The pedal seems to be stuck and it will not even move enough to make my brake lights come on. No matter how hard I push on it nothing happens. The parking brake works fine. I was told that they are sticking due to the length of time it's been sitting. My question is "How do Iget the brakes freed up?" I hate to send a technician that far to do something I could possibly do. Any suggestions???

 

Sounds like foot valve to me,might have froze up or something.

 

I would call the dealer or a 24 hour shop and ask them for advise. Worth a shot. Maybe some WD40 on every place you can see and get to. Maybe moisture caused some rust to build up and is acting like glue.

 

If your parking brake works I would have to agree with SCANIA. Your foot valve is either on the fire wall or below the floor. Either way it is conected to the bottom of the brake pedal and maybe in your harsh environment that you work in (limestone and dirt) the plunger has froze up or even the pin that hold the pedal to the bottom braket has froze up. I would take some Brake-Away and spray both. I have been staying away from the PB Blaster brand spray because I had it disolve some rubber o-rings.

Mike

 

usually when the pivot pin seizes, you will first experience problems with the service brake not releasing following a brake application

if it's a floor mounted pedal, the pedal bracket could be falling apart from corrosion destruction

if you look at the pedal closely, you should be able to move it a little bit despite the foot valve's plunger being seized... can you move it at all by hand... like pulling it upward or side to side?

if it's the valve that's sticking, i would still replace it even if the penetrating fluid does get it moving, it's bound to come back next time it sets for a spell