Those that have tuned or programmed

I actually have towed more than what my 3.42 standard output Cummins truck was designed for on multiple occasions when transferring our cabbed John Deere 4020 tractor between properties about once or twice a year for the past five years because my father-in-laws F350 6.0 was not up to the task. Now that he has his 2019 F350 3.55, he tows it, but requires a lower gear at a higher rpm than my truck to do so.