When I had my 2004 F150 Crew Cab w/ the 5.4L it had a payload right around 1600#.
Ended up 200# over my GVWR rating pulling a barely 6000# trailer with 650# of tongue weight (plus 3 passengers, a generator, firewood, tool boxes, etc)
Which is why I now own a 2500HD with a 2800# payload
2013 GMC 2500HD Crew Cab SLT 4x4, 6.0L
2016 Jayco Eagle HT 29.5 BHDS