What we have is a over reaction here. There would appear to be two issues here. First of all you have a safety issue with how much the camper would raise the center of gravity up (probably been sued recently for a roll over)... especially on a 4X4. Second, you have a emissions standards issue (aerodynamics changes can effect this). DC seems to be protecting themselves from both. I doubt seriously this is a structural issue, if it was I think someone here would have brought it up already. Has anyone checked the Chebby and ferd sites to see if they have similar... . qualifications?