There is alot of talk out there about various aftermarket adds for the duramax(I'm running a 2500 HD Crew). What I'm curious about is what kind of MPG increases are people seeing. I recently added the edge juice with attitude and have not seen much of an inrease in MPG(the first couple of weeks was lower and took a little off the tires too). I've experimented with the different stages on the edge juice and found almost no difference between stages 1-3 for MPG ( the power difference is very noticable). The truck is still breaking in (5000 miles) and I get between 15 and 19 MPG depending on my speed. At 70 mph in stage 1 I'm at about 16.5 MPG . If anyone has any other comparison it would be helpful.