Shopping for a 3/4 ton, What fit issues should I expect?

I'm considering my 3rd F250 for my second Northern Lite. One thing I know: the old F250s could handle 2500# and a little more. My 2011 has more torque and higher payload than my 2001 7.2l. The new trucks have bigger payload and more hp and torque. I generally put 10k miles per year and cross the Rockies at least once a year. No problem.

I wonder if anyone out there has carried a truck camper in the gas F250 which has 15 less hp and half the torque of the new diesels?