I have a recommendation of a service company as there is enough negative comments around here.
Went to move the coach and couldnt get the parking brake to release. After talking to the guys at Freightliner I called Coachnet. They sent out Speed Wrench Inc from Hudsonville, MI. Great knowledgeable service.
Recreational Vehicles - Speed Wrench, Inc.
"Speed Wrench specializes in mobile repairs and maintenance performed on location."
My problem was just a small air leak in release line.