Assuming that it is a monaco class a Diesel Pusher it will have air bag suspension. I am not an expert on Air bag suspensions but I have read about a self adjusting pressure regulator for the air bags that adjust the pressure to them based on chasis movement. If I understand correctly their is an arm near the air bag that contacts the chassis as it moves to lower or raise the pressure in the air bag as needed. If you have a 5 year old coach with less than 10,000 miles on it then it has probably set quite a bit and one of these arms could be stuck in position and not moving. This article explains what I am talking about.
How to Service Your Diesel Pusher RV
It could very well be one of the problems the other posters have mentioned this is just something else to check.