When I drive out of a driveway, from one level to another level, or into or out of a parking lot onto the street, something under the unit goes clunk. Maybe not a clunk. But it's like there's a bolt, maybe a big one, that is slightly loose, allowing whatever it is that it's holding together to shift a fraction of an inch.
It's been doing this for a year or so and now seems to do it more often.
I've slid on my back under the entire unit, with a wrench, tightening bolts here and there. Nothing has made a difference.
It's a 2017 Jayco Melbourne 24M, with 32k miles.