Chuck: assuming you can see pinkish-orange colored anti-freeze in the coolant recovery bottle, then you don't "need" to do anything to protect the chassis from the cold.
IF you have not done an oil change recently, I would recommend that you drain and refill with "fresh" 5W30 motor oil. Then you will want to replace the oil again when removing your coach from storage to get rid of the water that can accumulate in your crankcase due to condensation.
Also, whenever parked for extended periods, it is a good idea to put a rubber mat "moisture barrier" under all the tires. I use inexpensive automotive floor mats between my tires and the concrete to prevent tire problems. ED