I'm kinda late on this thread I know but seemed like a lot of reasonable people here so wanted to get some opinions...
My goals for my truck (07 megacab 3500 with the 5.9 Cummins/auto trans) is to raise the MPG and have longevity/low maint costs. I'm not a racer and rarely pull much of anything heavier than a car trailer or small box trailer. I put a lot of miles (700 miles a weekend on the interstate plus driving during the week) on my truck. I am curious what you would recommend for my truck with those goals in mind and what I would be able to see from such mods. right now the truck is bone stock except for fluids and I am looking at CAI, possibly EFI live tuning, possibly the water/meth kit, possibly a bigger turb (doing research on that now) and maybe a free flow exhaust. I will be doing a light build to the trans later on to make sure it is in good shape and shore it up for the long haul. Right now I get about 16 in town and 18.5-20 on the interstate. to get that I have to keep my RPM around 2000/73 mph.
thanks for any info you can provide/thanks for pointing me to another thread with the info if it has been covered already. seems like most people are looking for the hotrod truck they are getting rid of in a year or two, I want to keep mine till the floorboards fall through...