Welcome to the forums!
Put lots of blocks under the trailer wheels?
Actually, there is a product that works very well in this situation.
Sewer Solution. It will actually pump stuff uphill.
Another option would be a power macerator. Something like the
Flo-Jet.
I bought a Sewer Solution 15+ years ago from the guy that invented it to use with my Airstream, which had a very low sewer outlet. Still used today with my current rig.
Aaron
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