I have a 2014 36FK Seneca. The drivers side sets approx 2" lower than the curb side. Jayco says it is because of the 13' slide and the generator on that side. Freightliner says nothing is wrong with the suspension. I would like to know if this is common to the 36FK.
Our 2015 37FS does the same, but on the road it's level, I'm assuming, due to the air ride suspension on the rear axle. Doesn't seem to effect the leveling at a campground. I'm trying not to store much on the driver's side.
2015 Seneca 37FS
2015 Wrangler Sport
Our 2010 Dynamax on the M2 chassis leaned toward the drivers side. When I had it into the shop to have the driveshaft balanced they said they noticed it was leaning and they straightened it up. I got the impression the chassis is designed to be adjusted.
That's one thing that I checked for with our TS on delivery. Our TS sits nice and straight. If I were you I would call a Freightliner shop and ask them if it can be adjusted.