Forgot to add that the fx4 most likely has 3.73 gears which will help his numbers. Also has thicker tires which have a higher load rating and the stiffer shocks of the fx4 probably don't hurt either

 

ah i see. thanks for the info. still pretty confused but at least i feel its a more contained confusion..

 

if that is so why couldn't i put on better shocks and tires and increase my overall payload? i have been told on this forum your payload is what it is and can never change.

 

That has nothing to do with it. The FX4 in this case here actually has the lower GVWR.

It's true that you can't change your official payload number or GVWR. You have what you have.

 

Weight difference between the 5.0 and the 3.5 engines?

 

I think the 3.5 is something like 20 lbs heavier, so that would not explain it. At least on Ford's payload chart it looks like that.
Here is one example:
Regular Cab 4x2 145" 5.0L V8 8200‡ 3120
Regular Cab 4x2 145" 3.5L EcoBoost® V6 8200‡ 3100

As I said before: it's extra options on the platinum that cause the truck to be heavier by more than 300 lbs.

 

Maybe the rating goes up if you can turn on your fog lights with no running lights lol

 

Maybe the weight's of the 20's vs 18's come into play. Let's see what weigh's more rubber or metal!

 

That's just my guess. As for ur load capacity, the official number will not change as said earlier, but if u were to add heavier duty rims, tires, shocks, leaf springs, etc., u will be able to carry heavier loads

 

Power retractable step's w/motor may do it