I'm not sure if this is a common problem but it seems like the holding tank drain on my 94 Monach is lower than many other coaches. As often as not it ends up too low to drain directly into the sewer hookup provided. Even when the jacks are down on roughly 3" pads the drain fitting is too low to allow use of typical sewer line supports.

Trying to figure out if there's any way to correct this. Any thoughts welcome.

Have the same problem on my Regal
I just try to get the hose as high as possible exiting the bay and either use blocks or the slinky trestle to slope to the outlet
My coach is on a F53 chassis and rides very low
One positive though is that it rides great on the freeway and has little reaction to semis passing

Neil