We are doing it backwards. We bought the truck first and are now considering a TT. The must have for the truck was the 3.92 since I have the 7500lbs GVW cargo trailer. I previously had a 3.21 and six speed transmission and it really had to work pulling the fully loaded trailer through the Smokey Mountains.
Thats not really backwards IF you buy enough truck. I see the point of “get the trailer first“ however most people go through a gradual succession of rv’s. They start off reasonably modest size-wise and as their families grow or needs change then they adjust up.
Personally, I had a 1 ton 4x4 crew cab (1977, they did make em’ back then, 8’ bed too) and I started with a truck camper, then a 24 tow behind trailer, then a bigger truck camper, then a 28’ tow behind, then a class C. The truck was kept through the whole thing, but then it started off as a 1 ton CC so I had the weight and people hauling capacity.
Where a lot of folks make a mistake today is buying a luxo’ cruiser nice-riding 150/1500 super short bed, then to their dismay they find out there’s not a hard sided truck camper they can carry (builders lie and say you can but only a very selected subset of trucks, or highly modded). And it’s difficult to find a fiver that’s over 26’ to legally tow due to pin weights.
Now if they had a 6’4” bed, 250/2500 gasser, they could tow/pull/carry roughly 80+% of what’s out there without a problem. A 350/3500 single rear wheel (SRW) can tow/carry/pull probably 95% of everything except the real monsters.
Now there’s a subset of folks who will tow anything on axles with their 150/1500 and dare others to stop them. I saw alot of those on the f150 forums.
(Just because your engine has the oomph to pull a trailer doesn’t mean you should!)
Have fun picking your rig and enjoy it. Slow down driving and watch your loads. You’ll be fine.