brakes

I think on a 379 it's directly hooked to the pedal if it's the foot valve. But I have seen other things cause this spongy pedal. It's hard to explain here on the forum. I have seen very few foot valves bad in my day.

 

If you've been driving trucks where the pedal goes to the floor, that's not normal. Please bring it to someone who knows what their looking at. I think it's the foot pedal, which is not an easy fix. Let a good shop do it. It might cost you a couple of bucks, but it will be done right. If it's not the pedal, they will find the problem.

 

I agree.

Don't try to fix this yourself, TOW it into a shop NOW.


if you have to run it, then god help anyone you hit.

 

Yeah there are many different valves that it could be the foot pedal, what some call an r12 heck could be a clogged airline it needs to be checked out by a mechanic