I've had to do that before. Sloping down on the front: I've used wooden blocks under the tongue jack but the yellow blocks will work too. Just stack a bunch of them up until you have enough to level it front to back. If you have to go up a lot, wood might be safer.
Sloping down to the rear: I've had to set the tongue of the trailer on the ground before to get the trailer level.
2016 6.7 CTD 2500 BIG HORN MEGA CAB
2013 Forest River 3001W Windjammer
Equilizer Hitch
Honda EU2000
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