"Porpoising" - How to Tame the Rocking Camper

AndyRodagin wrote:

Grit dog wrote:
And feeling some weight transfer back n forth once when you hit a big dip or bump in the highway is not porpoising.

How about no big dip or bump necessary for the TC to oscillate like a rocking horse. No concrete highway with expansion joints necessary. Just driving down the road. When I DID hit a big dip the cabover slammed into the cab roof.

What then IS porpoising?

I'd say that is a poor setup, but you could call it proposing or whatever. But what you're describing doesn't involve the truck's suspension, it's actually a combo of both components flexing too much or not enough clearance between the overhead and the roof.