I have a 2011 f250 CC long box and it seems after hitting bumps in the road the cab bounces quit a bit it causes the dash and everything to shake if i watch out the back window i can see the bouncing is related to the cab moving the box stays perfectly still if you sit in the box the ride is much smoother and you can watch the cab bounce up and down i believe my cab mounts may need replaced does anyone have experience in having cab mounts replaced and making a difference in ride quality the current bouncing is really loosening up things and making rattles And no way can you have a conversation if the road is segmented the cab seems to be moving to much.

 

Could be as simple as over inflated tires, a seized shock or damaged bushings supporting the cab. Some things to check.