what do you mean by "fit"? the rad mounting on any size/year TF conventional cab truck should be the same .... the factory assy manual shows different rad #'s for 3000 series vs 4/6000, meaning one is HD to suit heavier use - it's still a 6cyl tho, and the core support is the same, so I'd expect if you're not going to be haulin freight up steep grades daily, any TF rad will "fit" .... an AD rad is a different animal and the core support is different
Bill