When you load the truck wand trailer drop by the scales and weigh the trucks front and rear axles separately with special attention to the trucks 6100 RAWR as its carrying about all the load.
Fords 17" tires may be good for around 3200 lbs however Fords 17" OEM wheels are rated at 3195 lb so don't go over about 6390 lb on those 17" wheels.
Now if you have the 18" or 20" option then those OEM wheels carry a 3590 lb rating or around 7000 lb on the rear axle.
Above those 7xxx numbers and you may have to mod the trucks rear suspension with higher rated wheels/tires and maybe air bags to safely carry the load.
Scale numbers always tells the actual weight story.