What trim package do you have on the F150? XL, XLT, Lariat, Platinum??
All of that adds weight depending on what the "shipping weight" is based on..
My trucks registration shows a 'base weight' of #4500.... ha, ha!! It really weighs around #5500 as it sits in the garage.. It's only an XLT, but is a SuperCab, 4x4 and I'm pretty sure that 'base weight' does not take that into account.... ;) Oh, it's only got a GVWR of #6250, so I don't have much payload...
Anyway, 'shipping weights', 'yellow sticker weights' only count for so much and what YOUR truck actually weighs can be very different... I know I pack way too much stuff than I need, but like having it, so there you go... :)
Once you get an ACTUAL weight ticket, you don't really know what your truck weighs... ;)
Good luck!
Mitch