Pusher axle issue....

the plumbing is either wrong or your valve is bad

 

New truck?
I have a Brand new freightliner with a factory lift axle was all run thru the computer.
Had to let the dealer hook it up to their computer to diagnose.

 

yes what is this on?
Lift axle is pretty simple, there is a valve that one way puts pressure to your down bags and releases pressure from your lift bags. then when switched does the opposite. there is probably a pressure regulator for down pressure that you can adjust and I'd guess there are quick release valves on the down and lift bags. the quick release valve just helps it move faster, I don't think they are necessary.
So start following air lines and see where everything goes. find your lift valve.

 

W&C - W&C Suspensions - Heavy Duty Truck & Trailer Suspensions & Axles (wcsuspensions-intl.com)
If you go to Tech Lit and then Air Control Kits there are schematics of the systems they make.
Need Help? Call 1-972.838.1266 or Email Contact Us
You could also contact them for service info but they may try to send you to an authorized service center.

 

yeah probably a manual regulator to control the pressure you're not seeing
if its auto regulating, good luck with that