I was organizing my spare parts today, some inherited from the PO and some purchased. I tried to find this on the internet to see what its used for so I could catalog it, but no joy. Some sort of Hydraulic solenoid?
looks like a coil for air leveling.
That's the coil for a solenoid. DO NOT apply power without the solenoid being inside or you'll be able to throw it away with a clear conscience. Ohm meter is okay: full voltage will burn it out without the metal being inside to cause magnetic eddy currents.
Could it be a coil for the fresh water fill valve.
Google "6359763"
Might have been purchased by the PO to use as an emergency substitute for a burned out HWH solenoid coil?
Google 6359793 0401 12V DC Coil
Or: https://www.hwhcorp.com/ml11428.pdf
That's what I'm thinking. It doesn't look like the HWH part used in the 6-pack. I have a couple 6-pack rebuild kits and an extra solenoid assembly, so maybe I don't need it. Definitely seem to be for an air solenoid, so the only other thing I can think of is the air brakes, but I haven't poked around under there to see if that's the case.
Don't waste your time looking for that on the brake system.