I need something with lots of seats and headroom. I'd like it to be able to tow as well.

Why does Ford knock 2,000 lbs off of the tow rating for a Wagon vs. a Van?
https://www.ford.com/resources/ford/...ansit_Sep7.pdf

example;
ecoboost 3.73:1 regular medium height;
6900 lbs towing in the Van, but add some seats to it and it shrinks to 4900 lbs.
seeing that I am considering an RV trailer over 6,000 lbs, it matters to me.

and for an even greater slap in the face; the same engine, WB and gears gets you a tow rating of 9300lbs in the Expedition EL.

It has me thinking of getting a Chevy and its 9600lb tow rating or maybe even a Nissan and its 8690 lbs.

 

I've been asking the same question for nearly a year. On another forum this was debated, and the consensus was that the added weight and COG of passengers could be hazardous to stability. I wouldn't hesitate putting a trailer like that behind my Transit though. Lots have towed over the limit and posted great results.

The long wheelbase model will be much better at controlling a trailer than the short wheelbase.

Sort of. It's likely the same physical engine, but in the Transit it makes substantially less power than in the pickups or Expedition. Only 310 HP/400 ft-lbs for the Transit, which is down from 365/420 in the Expy and F150. I think that's largely because these are tuned for a commercial duty cycle.

Take a drive in the Nissan. My wife and I test drove one and were absolutely blown away at the NV3500 SL. Automatic climate control, heated seats, parking sensors, and lots of other gadgetry that you can't get in a Transit. The long nose, shorter interior, and abysmal fuel economy made us choose the Transit. We aren't sorry that we did, our Transit has been great for our use.

 

My fear is blowing the transmission in the mountains and the local dealer would prefer to make the good "Customer Pay" money for a R&R instead of the peanuts Ford would pay and all they would have to do is look at the RV trailer to know it was over 5000 lbs.


ps. the non-boosted 3.5 in the F150 is rated to tow more than 7,000 with 3.73 gears

 

The transmission is about the last thing I'd worry about. The 6R80 has been used in F150s since 2009, and it's a licensed version of the ZF 6HP26 thats been used in foreign RWD cars since about 2001. It's tough as nails, very rare to hear of them failing even in highly tuned trucks that tow far more than 5,000 lbs.

Get an OBD reader of some flavor to monitor your transmission temps and you'll be fine. Towing our 3,500 lb boat the transmission has no trouble at all staying within ten degrees of the thermostat set point.