parking brake was engauged,I removed rear cans to release parking brake and when I ran the truck I noticed the regular brakes did not have air assist.can anyone help with their knowledge of these trucks.? I believe the dump is a gurling system,
The Girling brake system does not use air, it is powered by the power steering pump along with the steering, the park cans can be caged like an air spring chamber. They are pains, when they work, they kinda work, and when they don't, they really don't. It uses Hydraulic pressure from the steering pump to apply the service brakes, as well as overcome the spring pressure that sets the park brake. There is a small electric motor that generates a limited amount of pressure attached to the booster assembly on the firewall. If you don't have any assist or park, I would determine that it has plenty of fluid in the pump. steering pump that is, it takes dexron atf.
87 f800 dump bvfdfire,thank u so much.there have been other people who directed me in the wrong direction.what u say makes perfect sense.when I removed the cans the park brake released.the brake pedal was solid and took everything I had to stop truck.i will do as u say and look at that motor on fire wall...thank u again sir...