06' 780, rear air bags keep inflating sending ride height way too high.

Hi all, hit some rough road in SC and the ride height went crazy all the sudden causing some very bad vibrations (I assume because of the effect on the drive line). I just replaced the dryer because it was a mess (carboned up bad) when I went to change the canister, the leveling valve seems to work ok when I operate it by hand with the rod disconnected but when its hooked up it doesn't seem to shut the air off to the bags. anyone have any ideas of what to look at next? have any of you ever ran into this before? I haven't seen anything damaged or anything else like that. Also, what would be a normal average bag pressure reading, this one was as high as 117 when I noticed it and seems to be currently around mid to high 80s to low 90s (front) and 20-40s (rear) (rear was also over a hundred when it happened) according to the truck info on the dash readout. Appreciate any help very much.

 

Thanks all for the input, big help, leveling valve is now 1st on the todo list in the morning.
I have another question though; while I was doing the dryer replacement I notice 4 what look like valves on the cross member behind the transmission (they have 2 wire twist lock plugs going into them at the bottom and 1 airline each coming from the tops with a main supply line on the right side) I can't seem to find any information on these, any ideas what these are and do? they look like maybe some kind of check valve or solenoid.

 

Will do.

 

[GALL[GALLERY=][GALLERY=][/GALLERY][/GALLERY]ERY=][/GALLERY]

 

Best I could do for a pic., guess I'm not as smart as my phone.