I own a '03 Ford F-150 4X2 Supercrew 4.6L with a 3.55 ratio limited slip axle. I am purchasing an Attitude Toy-Hauler (23AK) that will weigh approx 7500 lbs when full of toys (2 1/2 quads), water and fuel. With the 3.55, the owners manual has two entries for maximum trailer weight: 6600 and 6900 lbs.
First - why the two weights? How do I determine which applies to my truck?
Second - If I replace the current 3.55 with 4.11, what does that do for me in regards to additional weight I can pull?
Third - If I move up to 4.56, would that be a smart move?
Fourth - Don't say buy a bigger truck, I can't afford it at this time!!!
I understand that with increasing the ratio, my low end will be better, but on the high end I will lose power and speed. When I am not pulling the trailer, is there anything I can do to get the power back?
I have also added a Volant Air Intake Cooler, Magna-Flow Cat-Back Exhaust, and have a HyperTech Pwr Pgmr. Truck has a 6" lift and has 33" tires. Any help you can provide would be appreciated.

 

with those 33" tires and a 6" lift my first ? is do you plan on putting larger tires on in the future? 4.10 would put you at about stock if not alittle over, 4.56 would put you 200-300 rpms over stock and is what i would recomend for towing with 33" and if you wanted to upgrade to a 35" tire in the futer, hope this info helps