working on a 2007 f650 d/t.
driver complaint red trailer air supply valve wont stay engaged-PUSHES BACK out when you remove your hand.
so I plugged off glad hand at tractor-not connected to trailer now. same problem. replaced mv-3 dual valve(yellow & red knob valves) . same problem. replaced tractor protection valve. same problem. also when red knob has air pressure, yellow knob wont stay in-engaged
driver complaint red trailer air supply valve wont stay engaged-PUSHES BACK out when you remove your hand.
so I plugged off glad hand at tractor-not connected to trailer now. same problem. replaced mv-3 dual valve(yellow & red knob valves) . same problem. replaced tractor protection valve. same problem. also when red knob has air pressure, yellow knob wont stay in-engaged
