What year is it? I had some ~2000 Ford F750s with Cats that were underporwered. I don't remember the rating. The Cat dealer was able to reprogram them to add a bunch of torque but not much HP. Adding HP would have required new turbo, etc. ANyway, my drivers were very happy with the change. As Thomasbus24 mentions, Cat said I first had to check with Allison to make sure my transmissions would be OK with the change before they would do it.