We stopped for a few minutes and as we started to get back on the road we were greeted with a big air leak. Just as I released the parking brake there was a big air leak. First thought was something with the parking brake. The Aux air gauge was dropping very fast all the way to zero. The problem was the 10 year old bellows in the air ride seat blew out. Add another air bag to the 10 year replacement list.
The important part is that with no aux air the parking brake will not release. If the bellows blows while driving in about 2 minutes you will be parked even if its in the center lane of the interstate.
I plugged the line to the seat and got air back.