How about a vehicle made for towing so you don't put added stress on the X? Just my opinion, I haven't done any research on the specific topic at hand. However, I do have some experience with full size SUV's, pickups and mid-size SUV's with towing. The FS SUV's and pickups always outperform the midsize ones. Perhaps you can pickup a dedicated used pickup for towing for cheap?

I have never towed with my 4.8 but I'd feel much more comfortable with a full size truck rather than my X...

Good luck!