I use a Ford F-250 Super Duty, extended cab, 8 foot bed. I do not have a dual rear axle. No problems in about 15k miles of trailering. Duallies would probably help keep the back end of the truck planted and tracking well when cornering, but I just make sure I slow down enough beforehand. The tow capacity is 10k lbs which should just fit a J30 and a trailer in under that number. I have the diesel which gets about 8mpg on the highway. A friend used the V10 gas engine and got about 5mpg.
