Don't panic yet. The only time the front surface area comes into play is on the freeway at speed. If your Jeep is rated GCWR, GVR, etc. within specs, it will do OK. What you get at freeway speeds is wind resistance. It goes up with the square of the speed. If it doesn't overheat your Jeep, it's probably OK. If you are towing, the speed limit is 55 (here in CA), so you are not likely to get a huge wind drag. If you plan to do 65-80, well that's another issue.
I would try it and keep an eye on the temp. gage and the power performance.
2004 Tiffin Allegro 27.5 ft. P32 18,000 lb GVW. 8.1 liter. Workhorse chassis built May 2002. 21,000 miles. 2012 Jeep Liberty Toad. RVi2 brake unit.