[QUOTE=TPF Hunter;8868256]
Thanks for all of the replies. I need to correct my initial post and got confused saying which truck we were looking at. He was looking at the New 3.5L Eco-boost F-150 V6 and said the “towing rating was fine”. The 3.7 liter was another truck he had looked at previous so my apologies for the mix up.
Looking at Ford’s towing ratings (link provided) for the truck we are looking at (Supercrew most likely), it says anywhere from 10,000 - 12,000 pounds. Which is higher than the V-8’s towing rating. Knowing that - would you haul a 2 horse trailer and two horses in it? Would be mostly local miles or up to a 2.5 hour haul at most.
http://www.ford.com/trucks/f150/specifications/towing/
To answer one person’s question - I am very much so not new to the scene. I am used to hauling with a F250 or a F350 dually but neither of those trucks are available to be used anymore. They belonged to family members that decided to sell, which is why we are looking to purchase a daily driver that could also haul on occasion.[/QUOTE]
The “tow rating” for any given pickup is pure, unadulterated, night soil, bovine, male!!!
It’s a number from Marketing, not Engineering.
The ONLY number that counts when discussing towing is the GCVWR (also known as the GCWR). This number is the MAXIMUM that the truck and tow can weigh in tandem.
I just put this in another thread on the same subject. I’ll repeat it here for convenience:
You’ve got to weigh the truck. Find a local truck stop with CAT scale and that will cost you in the area of $25.
Let’s say the truck comes in at 6000 pounds. That means:
12,100 [GCVWR for the vehicle in question] - 6000 = 6100
Your real towing capacity is 6100 lbs.
6100 - 3900 [weight of trailer being discussed] = 2200 lbs.
That’s your “useful load.”
The GCWR is calculated by the engineers for a “dead” load like a boat or a load of hay or a travel trailer. Horses and liquids are “live” loads in that they can, and do, move around. If you load to the maximum you have no “J” factor. If something goes wrong you’ll be at the end of your “operating envelope” and that might mean bad things happen.
You find the GCVWR/GCWR in the Owner’s Manual (or sometimes on the driver’s door post). This is the LEGAL limit that you can have with truck and trailer. It may be larger than the practical limit you should have.
The short answer is that it’s highly unlikely that this truck would be suitable for pulling even a Brenderup with one horse.
But tell your DH to keep in mind the First Rule of Towing Anything: Starting Is Optional; Stopping Is Not. So it’s not the engine and drive train that are critical, it’s the braking system.
Your money, your horse, your butt, your choice. 
G.
*In the original thread numbers for the truck and trailer had been already discussed; italicized explanation provided since that context is not clear from my response.