Found this, not exact as it has a QR in the front and not a relay valve. I'm thinking that if you call Wabco they should have one with your system. Great for future reference. Note what it says about the rear relay valve leaking with the brakes applied. I agree on replacing the R14.
tp9973_web_en.pdf
2019 LT Air Leak at Front Relay Valve
Discussion in 'International Forum' started by JeremyTourville, Jun 8, 2025.
Page 2 of 2
-
-
Trucking Jobs in 30 seconds
Every month 400 people find a job with the help of TruckersReport.
-
-
I wanted to say that I have it all fixed now. I bought a service kit with all the o rings, seals, valve seat, spring, etc. It turns out the rubber diaphragm was blown out. Somehow I missed that during my initial inspection. The kit was about $50 vs $250 for a new valve from the parts house.
FWIW, this turned out to be a common theme on my truck. I recently fixed a leaky tractor protection valve on my truck for the same type of issue. The diaphragm there is the same shape. (Not sure about the size though). Anyway, some flat sheet rubber of the correct thickness came in handy. I traced the old part and cut a new one.Attached Files:
-
Trucking Jobs in 30 seconds
Every month 400 people find a job with the help of TruckersReport.
Page 2 of 2