Shaving cream!
Hook it and go! I bought a 285/305 rated V6 in a full size half ton a couple if months ago. Granted I have yet to be above 700', I've had no issues towing a 6500 and a swag 8000 lbs of concrete mixer trailer behind me. It does every bit as well or better than my BB 454s pulling the 6500 lb trailer.
You have a turbo as noted, so you have sea level HP up to 8000-10000' if elevation. Said V10, 454s, and my V6 lose 3% per 1000' gained. In yellowstone at 10,000', you still have potentially 100% of your HP, those others have lost 30%!
Get w rounded trailer body, keep frontal are to 60-80 sq ft, I'm having a hard time thinking you're going to have issues. I probably would have bout the 300HP turbo I4 gm has in their1500s if anew truck was in my budget. Alasit was not, so a used truck it is. I would have no issues towing a 4-6000 lb trailer aerodynamically designed with ANY of the current model turbo 4 banger or the V6 like I have.
Marty
