I have an 02 Expedition EB Edition that I purchased privately in August. Since we got it, it's been leaning to the right(Passenger side). I believe it has to do with the air ride suspension. When compared, the left rear wheel well is further from the tire than the right(thus the lean to the right). I don't know much about air ride suspension. But from what I've found on the net, it can be one of three things: the Air bag spring is leaking, the airspring solonoid is bad on that side, or an air leak somewhere else. I have not detected any leaks, so this leads me to believe the solonoid is bad. Is there any way to check the solonoid(like checking the resistance)? If so, what are the specs? Any help would be greatly appreciated.

Thanks,
John Germany