First thing , would be to contact Spartan for an " air system " diagram, that diagram will tell you if your chassis has a single or dual air leveling valves for the front end. They should also be able to give a part number and location of the valve ( s ).
NOTE; dropping in 5 hrs is a major air leak , and it'd be dangerous to be under the coach for leak testing , you could be pinned or crushed.
Spartan Motor Home Support .
1-800-543-4277
Have your chassis serial number handy.