It should be pretty level. There was an interesting article in Trailer Life about RV fridges, and they suggested getting the trailer as level as possible. We have posted here that the fridge should be level side to side, but not as important front to back. After reading that article, I think we should just settle on "as level as possible". According to the article, being off level seems to be the number cause of failure.
I moved the thread to appliances and electronics.
Chap , DW Joy, and Fur Baby Sango
2006 Ford F150 Super Cab 4x4
2008 Surveyor 263