If you have narrowed down your choices to a Yukon or Tahoe, I would suggest the Yukon. We own a Bentley Tritoon and a travel trailer. Our normal tow vehicle is a 2011 Yukon XL. This thing tows like nothing. With 7 people in the car and all our luggage, we towed our travel trailer, weighing in around 5000lbs from east Tennessee to the beach and averaged 12.5 mpg. Pulled it with no issues at all. We purchased our Bentley in Kentucky, about a 3 hour drive. We used my In-laws 2014 Tahoe to go pick it up. It was pitiful to say the least. With 4 of us in the car, we averaged 8 mpg and even in Tow Haul Mode, the transmission stayed in passing gear pretty much the entire trip. I was worried we were gonna break something. Both have the 5.3 with the 6 speed transmission. The only difference the rear end gear. The Yukon just seems to handle the towing alot better.