Originally Posted by Captain Bob
. Anyone have towing experience with the 3.5L NA engine?
Not me, but I've noticed that Ford's GCWR numbers are a really good indication of the relative towing power of their vehicles.
With 3.55 or 3.73 axle ratio, the 3.5L EcoBoost has GCWR of 17,100. With 3.73 axle ratio, your 3.5L NA has GCWR of 12,200. That's 71.3% as much towing power without the complications of the twin turbos and need for premium gas for heavy towing.
In real life, the tow ratings are based on an empty truck with no options other than those required to achieve the GCWR, and nothing in it but a skinny driver, a full tank of gas, and nothing else. Tow ratings are 7,200 for your drivetrain and 11,800 for the Ecoboost. More realistic for an empty tow vehicle is a max trailer weight of about 6,500 for your drivetrain and 11,000 for the EcoBoost. And more realistic for the way most folks load their tow vehicle with family, tools, campfire wood, etc, is a max trailer weight of around 5,000 pounds for your truck and 9,500 for the more-powerful EcoBoost drivetrain.
There is a huge difference between a wet and loaded trailer that grosses 6,500 pounds and one that weighs 11,000. But as long as you stay below about 6,500 trailer weight and with nothing in the truck but a skinny driver, you should not have any problems with being the slowpoke holding up traffic on hills and mountain passes.