In my 1994 U300 I was having some issues with it staying level. I noticed that in manual mode, it would be ok, but in travel mode it would not stay level. I assumed that it was the rear leveling valve. I replaced it and no change. When I went from high manual to travel, one side would stay high while the other side would go to travel height as well as the front. I went to the 6 pack air valves in the rear and located the 2 travel ones. Tested them disconnected with an ohm meter and found a bad coil. As I really didn't want to replace the 6 pack, I removed the nut and pulled the bad coil bobbin off. Moisture had gotten to it. I have had a lot of experience with this type of valve in my career. I found a new single valve on Amazon ($25) and purchased it. I pulled the coil out and it was a direct replacement inside of the can. Cut the old connector and spliced it to the new coil. Working fine now! US Solid model JFSV00051 12volt
Nice find and fix ^.^d