Yes, the fridge needs to be close to level as you can get it. Its an expensive item to replace.
If you place a level at any spot other than the fridge freezer, you have to make sure the fridge was installed level from the factory in relation to the floor .
On most popular floorplans, fridges are installed on the passenger or drivers side of the RV. It's important to know, because of the design of the fridges tubing, that the flow of liquid/gas is more important if the front to rear level..is level. If the side to side is off, its not as important because gravity and the location of the tube in relation to gas flow comes into play.
If a fridge is located along the front or rear wall, then side to side leveling is more important.
