I'm in the midst of finalizing a purchase of a 2016 XD, 4x4, Diesel w/Platinum Trim to tow my newly purchased Grand Design, 150 Series, 290BH Reflection, 5th Wheel Camper. I have researched and driven various trucks. Although these 5th wheels are apparently designed for F-150 towing, after 3 weeks of research (i.e., spec'ing out the heaviest duty F-150 at a dealer; reviewing actual F-150 driving tests posted on YouTube videos, and based on comments by 5th wheel owners of the same camper series), I believe the F-150 is too light. Meanwhile, my wife drove a F-250, and indicated that it was too rough for her, and that she wouldn't drive it. Further, the F-250 will not fit in our garage. As a result, I've zero'd in to the Titan XD Diesel, or Gas (it will "just" fit in our garage). My 5th wheel camper dry weight = 8,194 lbs; the GVWR = 9,995, and the king pin weight is 1,280 lbs (dry weight). If I pack a 1,000 lbs of liquid and cargo, obviously that's 9,194 lbs loaded, and at a proportion of 20% that's 1,838 lbs (theoretically), on the pin. I have no concerns as to whether the truck can "Tow" it - at least based on Grand Design 5th wheel Facebook owner group comments. One owner has pulled a similar 5th wheel camper, with another 100 lbs of pin weight for 2 1/2 years to Texas, the Carolina's, Florida, N. Michigan, and Illinois) with a 2016 XD Diesel, Crew, Platinum trim (same truck as I'm considering). He did have the dealer add another leaf spring. The only confusing part for me is Payload. According to the 2018 (don't have the '16 one) Nissan brochure, the Maximum Payload for a 4x4, Diesel, with Crew, is 2,000 lbs, and for the Gas it's 2,520 lbs. I prefer the diesel for towing, and mpg when under tow. However, with the 1,838 lbs pin weight, plus another 4 passengers at say 720 lbs, that's 2,558 lbs in payload weight. The owner that I just mentioned says his payload rating on his diesel is 2,900 lbs. ??. Further, I sent him the exact diesel truck that I'm considering purchasing (which is the same as his). He says that it's "plenty of truck for your 290BH". Hmm ???. How does his rating say 2,900, when the Nissan brochure say 2,000 lbs. Nevertheless, he's towing about the same 5th wheel camper without an issue for 2 1/2 years (long distance), with a 2 inch rear wheel-well squat. Hmm ??? ... I have two questions: Scenario 1: With an extra leaf spring, do you believe the diesel can carry 2,558 lbs (safely)? Scenario 2: Alternatively, owing that the Gas has a rating of 2,520 lbs, would you buy a Gas, knowing that under tow they get about 10 mpg, vs. 18 for diesel? And I hear less than the diesel around town too. I would greatly appreciate your practical and professional opinion related to my two questions, and any other insight. I'm trying to buy the right truck!!