While I agree that you should check your setup, there is a HUGE difference between a passenger vehicle (expedition) and a heavy duty truck (F250). Simply put, the HD truck is made for hauling and towing.
When I upgraded from a 1/2 to a HD truck years ago, there was a huge difference. I am a Dodge fan, and there is a huge difference structurally between the 1500 and 2500/3500 configuration. While the outside body make look similar, internally, there's lots of differences.
Both trucks had plenty power, but the HD just feels way more solid.