My goal is to be able to drive SLOWER and maintain a SLOWER speed. If I start a small hill at 60 I am way down in the 50s by the time I top the hill. On a road with 75mph speed limit, that is just too slow. If I can start at 65 and top the hill at 62-63, I will be happy. Currently I can start the hill at 68-70 and top it at 65.
I don't know if I am making it clear or not, but I am not trying to pull the trailer faster. I just want to move the power band around so that it suits pulling a load at a SLOWER speed.
I still can't figure out why they put 3.55 gears in a truck with the RV special package.