Damn nice truck, I have read nothing but good about the spartan tuners on the 6.4, seen a few put down over 500rwhp. The noise level on the 6.4 is amazing, you can't even hear them running next to mine...hard to believe its a diesel when it is running at idle. As you found out, the worst part is the mileage...but that tuner and DPF delete should really help out.
On my 6.0, I can get around 18mpg if I keep it around 60-65 on the highway....that is with 3.73 gears and 38's. City driving is around 13 if I take it easy (which I rarely do). Pulling a trailer kills it though, last weekend I averaged 8.9 mpg's pulling my 24' flatbed with 2 quads and my RZR on it (total weight probably 5-6000lbs), which really sucks for a diesel IMO. Hopefully a set of 4.30's or 4.56's will help that out.
Originally Posted by farm_boy
they move but have all kinds of promles and stop erevy 100 miles for fuel i hate them hey your truck i drove a brand newe one as a plow truck this year