Plumbing trailer brakes

[1972RedNeck]

I've got a '65 GMC civilian fire truck with air assisted hydraulic brakes. The air assist booster under the floorboard looks very similar to the one on our old Deuce. Is it possible to get an air brake signal off of the booster to run regular trailer air brakes? I assume I just need the signal to plumb into a tractor protection valve (tractor protection valve acts as a relay valve, correct?)

 

[topo]

I can take some pictures of how my truck is set up and post them in the morning .

 

[topo]

marked with the yellow tape is where the air line comes off the hydraulic booster and goes to the relay valve .The red tape lines go to the rear of the truck glad hand and to the glad hands for the fifth wheel trailer the green tape marks the air line from the hand brake control by the steering wheel .

 

[dmetalmiki]

I don't know why you talk about " Signals "..Or, Why you need to figure anything out using a military trailer with a military truck.
My Diamond, My deuce, My Wrecker, And my British Scammell tank trandporter ALL (Can) 'pull' My CP22 U.S. Army 22 ton trailer.
The U.S. Army Rogers and Dyson trailers are the same.
You hook up and go. NO! you Do not. (As) Untill the air pressure builds up in the rogers and Dyson the brakes stay firmly on.
The CP22 trailer you can pull away without air..
The RED emergency Line provide air to the trailer storage tanks.
The YELLOW line provides air to APPLY the trailer brakes.
Diamond T, No air NO BRAKES!
All (Most) others No air the brakes are applied.
OLDER trailers drain off the air and they CAN be towed.
Hope that helps you somewhat.
Read up on the Bendix air brake systems manuals.

 

[1972RedNeck]

marked with the yellow tape is where the air line comes off the hydraulic booster and goes to the relay valve .The red tape lines go to the rear of the truck glad hand and to the glad hands for the fifth wheel trailer the green tape marks the air line from the hand brake control by the steering wheel .

Great pictures. Thanks.

Where does the red line come from? Air tank? Or trailer brake release valve (red button)?

 

[topo]

The red splits at that valve one goes to the back of the truck for a trailer hooked to the pintle hitch and the other red is for when a trailer is hooked up to the fifth wheel each end has a on and off valve by the glad hand . there are no brake release buttons in the cab just a manual valve by each glad hand . the supply air line is tied in to a air tank with a hand valve by the glad hand there is no tractor protection valve .