My choice would be a 5.0 with 3.73 gears and a max payload package if I had the option to buy a brand new truck from the dealer. From everything I’ve seen towing with half tons is that you usually max out your payload long before you do the tow rating so I’d look for the highest payload rating I could find.

The 2.7, 3.5, & 5.0 will all pull your trailerjust fine and usually gets around the same fuel mileage while towing. The EcoBoost will make better power down low due to the turbos while the 5.0s love to turn the rpm’s while towing. My 5.0 with the 6 speed loves to cruise at 3-4K rpm’s with a 7-8k lb. travel trailer.

Also with the amount of pulling you’re looking at doing I would probably look into at least replacing the rear shocks with Bilsteins 5100’s and maybe keep a rear anti sway bar in mind for the future. Add a good weight distribution hitch to the list and the truck should be really stable while pulling. These are just the things I would do.

LT tires vs P tires is debatable and kinda just comes down preference as either will work fine with their own advantages and disadvantages over the other.

 

Yeah just bought a Roush Supercharger kit to help with this as you definitely feel the power start to really drop at 8,000 ft elevation. Went from Creed, CO to Lake City, CO which gets you up around 12,000 ft elevation going over a mountain and even without a trailer it feels like the truck has only half its power. I’d love to pull my camper further into Colorado from where we usually stay but I’ve been hesitant to do so before due to this reason.

 

Great you are looking at truck payload as well.

OP commented that the 2.7 leaves precious little truck payload available once loaded-and has kids that only grow bigger and heavier. The extra 450lbs offered by a 5.0 makes more sense. 2.7 owning buddy has towed a car with his truck and said it struggled in the interstate hills of VA.

I track transmission temperatures. I've seen in the 210-218 range towing on highways with nothing more than the regular tow package. 53C. Historically Ford has relied on the 5.0 for the Max Tow. I suspect its wary of the additional heat load of the Turbos on the drivetrain

 

And I towed 8,000 lbs with my previous 2.7 and there was no struggle what so ever.

 

It's all about payload. Any F150 motor will do the job. The light duty F150 frame (2.7 L) will be ok. And yes on occasion the 2.7L and light duty frame will do fine with a heavier trailer. When not trailing you will be really impressed with the power and fuel mileage. When traveling with the 4000# horse trailer what else will the truck be carrying? One passenger? Cargo? And always a but, how long do intend on keeping the truck? And the future: what is the likelihood of a regular use larger trailer? Four passengers? Best to go with 3.5L or V8 (both sophisticated motors), which gets you the more robust medium duty frame, and higher payload CCC rating.

 

Thank you everyone for the input, greatly appreciated.
I’ve decided on 3.5 with tow package. Should close the deal next week
Cheers

 

Ensure you look at the yellow door sticker for Cargo Carrying Capacity, the higher the number the more payload you can carry on the vehicle.

 

If you're at elevation over 6k, might want to run e85 for the power boost it gives you if your 5.0 is flex fuel.

 

Lets see a picture of your new ride when you have it!

 

Just have to add tint