New member having just read some good material by others about using the 3.73 gearing over the 3.55. I'm trying to build a replacement for my 2016 3.5 EcoBoost that has the 3.55 gearing however couldn't successfully create the build on the app and the local dealer says I can only get that gearing with an 8 foot bed. Can't believe this to be accurate after all I've read in these chats. Any thoughts would be greatly appreciated. Would really like the next eco boost to have the 3.73 gearing but a super cab 6.4 bed. The 2016 handles our 6,500 lb camper very well at 9+ mpg but all experienced haulers boast about the 3.73 gearing. Do I need to be that concerned? Our new camper will push more to 9,000 loaded. Maybe 3.73 not necessary.