I have a little bit of extra money right now, around $700 bucks to spend on the cummins, I would like to gain some mpg's so I was thinking either rv275 or a smarty programmer or edge comp. My trans is stock would it hold up with either one, if I had the programmer it would either be on fuel saver or tow mode. Also would I be better off maybe doing a shift kit first. I'm not looking for huge power or anything just some extra get up and go and mpg. But want to be safe right now on the tranny. Truck has 140,000 bought it second hand and supposedly new trans rebuild at 110,000 shifts good and no issues so far.

 

For the tuning edge does a good job on tuning for 24 valve. make a good easy to use product. smart driving your trans will last quite a will at those power levels.