2005 Western Sterling spring brakes won't release

Thank you, I'll pass this along.

 

Thanks again.

If it were me, I'd prefer one without ABS and all the extra stuff that can go wrong. I'll check out the truck and get back with more info. Think its got a Cat powerplant in it. Its got a modulator for the brake system (ABS) and a modulator for the spring brakes (secondary brakes?). Must be something simple like a stuck valve like you and others have said.

 

He got back to her and this was the problem, the foot brake valve wasn't functioning properly. On the Sterling the valve is floor mounted and he found that dirt and grim had worked its way into the valve.

Thanks to all who helped out! )