"appears to be in tact" Are you meaning that the auto height control actually works or that it looks like it should? In my limited experience, the most common failure points are the leveling valve first, then the compressor and then the shocks. That's about all there is to this system other than some air lines and a reservoir. If your leveling valve is shot, I replaced mine with that from a semi tractor trailer unit. It is very similar and it is called a NewWay valve. Any truck shop or truck salvage yard will know what you mean if you ask for a NewWay valve. I bought one from salvage for $20.00. I am told that Monroe part number MA757 is the appropriate application for this system. ----- Original Message ----- From: <IMPERIAL1981@xxxxxxx> To: <mailing-list@xxxxxxxxxxxxxxxx> Sent: Thursday, May 30, 2002 3:08 PM Subject: IML: NYB/IMP self leveling suspension??? A friend of mine has a 77 NYB 2 door (61,000 miles) with the self-leveling rear suspension system. Every thing appears to be in tact but the rear original shocks are looking somewhat aged. If they need replaced can we install regular air shocks in their place? Tomorrow we are going to adjust the self leveling mechanism and see what happens......there are no leaks in this system anywhere so it should do what it was intended to do.