Here's the numbers I'm running. I'm thinking (after upgrading the trans cooler) that a max GVWR I should be comfortable with for a trailer would be 7200 lb and a max tongue weight would be 720 lb. I came up with these numbers from the calculations below. Do they hold water? I'm also looking for feedback from those with similar vehicle specs who have real world towing experience close to those max numbers and how the trailer handles for them. Don't want a white knuckle ride (been there done that). Can anyone help me out (I have the 3.73 gear ratio)?
My calculations
------------------
TRAILER
7200 lb GVWR. (With tongue weight about 10% of total trailer, max tongue weight for Expedition is 860 lb and max trailer weight rating is 8600 lb GVWR. Take 15% off for safety and ease of towing cushion).
TONGUE WEIGHT
860 lb (max rating) - 140 lb (15%+ cushion) = 720 lb
GCWR
6580 lb (vehicle GVWR of 7300 lb minus my tongue weight of 720 lb) + 7200 lb (trailer GVWR) = 13780 lb (5% less than 14500 lb max rating)
VEHICLE
7300 lb (GVWR) - 5600 lb (Vehicle weight) = 1700 lb (Cargo weight max for in vehicle)
CARGO WEIGHT
720 lb (tongue weight for me) + 500 lb (3 extra passengers) + 300 lb (cargo in Expedition) = 1520 lb (under the 1700 so OK)
