The F100 was a 1000lb capacity truck. #100=1000lbs=½ton. The F150 was 1500lbs. #150=1500lbs=¾ton. Recently I noticed a F150 commercial and the capacity for todays F150 is ½ton!
The capacity of the F150 varies from 1500 lbs (3/4 ton) to 3000 lbs (1.5 ton) depending on which model you buy