The speed bumps that i have been through has cause dunkey kick on the rear suspension. i think around 50mph, driving like that cause the exhaust system to disconnect from the headers. I think is not nessesary to hit the stocks bumps stops what matter is the hit worse if you have the tire psi 41psi up.
From today i started to drive my truck as a normal f150, see and avoid square potholes and slowing down at speed bumps. Until i get leaf springs with 3.0 suspension and bump stop
You have to be hitting the bump stops in order to bend the frame. That's how it happens. Excessive force on the weaker area of the frame from the axle hitting it causes it to deform.