I'm told you can crank up the torsion bars in the front to raise just the front. Check into that.
New shocks might help too. You can buy 4 new monroes for under $200.
Also if you have the stock sized 195 tires on the front and 215 tires on the rear, it's not going to sit level.
The 195's are 1.5 inches shorter than the 215's.
I don't know why winnebago chose to use 2 sizes of tires???