noises in leveling system

[charlesebrownjr]

I never found an answer to mine doing this. It sounds just like a fog horn as you say. I think it is air pressure trying to equalize between the canister that serve the drive axel brakes. It just stopped on its own I think or, maybe it stopped after I had all my air bags and Norgen's replaced. Not sure.

[dmatz]

i had a similar problem on a bluebird and it was a check valve. just a thought.