Lots of people think that when they hear a gas engine spinning 4000 rpm, it must be "struggling".
The truth is, an engine that has a 6000 rpm redline is not really struggling at all at 4K rpm. Most of the noise you hear is the fan trying to pull air. You could probably argue that the fan is struggling.
A properly rigged Pathfinder, and a driver with realistic expectations, could pull that camper all over the country.
Or, you can take the other approach: one ton dually.