Your coach uses this filter....MERITOR WABCO R950011. It's a very common filter number and made by various companies. It can even be found on Amazon. Monaco used this same filter for years. It's located behind the vented door, just in front the driver's side rear wheel.
Use your brass drain vales in the generator compartment and the rear hitch to drain all air. Once drained, you'll probably need a filter strap to twist the filter off. An old leather belt and a pair of Vise Grips will also work.
Once removed, there should be no more than a drop or so of water in the filter holder. Put a light coating of oil or thin grease on the new filter o-ring and reinstall. You don't have to go crazy on tightening it. I'm a big guy and always use just my hands.
While you're in that bay, you'll also see the pump for the jacks. The way that Monaco mounted it was kind of goofy. They only bolted on one end and left the majority of the tank hanging in the air. I added a small bar under the rear of the tank, with a rubber piece between the tank and the added bar. You can bolt the bar on between the two rails on both sides of the tank.
Lastly, that jack tank will most likely be covered in fluid from the tank vent on the top. Remove that vent and add a 3"pipe nipple to it. It will eliminate the overflow, but still work as designed. Once you have it on there, use a degreaser and clean the tank up, as it won't get that dirty again.
Don & Mary
2019 Newmar Dutch Star 4018 (Freightliner)
2019 Ford Raptor