- 441
- 47
- 28
- Location
- Blythewood, SOUTH CAROLINA
The park brake dash valve is a Haldex KN20035. The trailer dash valve is a Haldex KN20025. On these first generation trucks those two valves are separate. On newer trucks they are integrated into a single valve assembly which is also serviceable. Maybe one day I will swap out the two individual valves for this single valve setup, I like the idea of being able to service it.
I have been reading through all of your posts in this thread. I have actually replaced all three of the valves behind the driver step cleaned the one way check valve behind the lower bumper grill and gotten the air leak to the emergency glad hand to stop. In the above quote you referenced the part number for the parking brake valve in the cab have you replaced this valve? Reason I am asking is because I cannot release the brakes on my truck if you attempt to depress the valve it springs back at you like it is pressurized also the truck will not build air and is exhausting all of the pressure in the transmission tunnel in a vent that I am guessing vents air from the parking brake valve. I have also taken the other valve off that is located under the same lower bumper grill. I am going to replace it as well because it appears to be bad air comes out of all the ports no matter which port you put air into it is plastic and not serviceable but I assume this means it is bad. If you have any more insight on my troubles just please let me know and thank you so much for all of the great info you posted.