Thanks for the reply, I just read about the how adding a programmer can shorten the life of your injectors, and being at 170,000 miles I think that I might be on borrowed time. I really don`t tow alot of weight just my camper trailer and a utility trailer. I`m looking to get more MPG, then power. But I also want dependability and not do any damage to the transmission. I had the clutch changed at 100,000 miles.