I see VG's ruffle feathers around here. For me, it is too late to quote Hucho and any other because I have been driving the proof of concept all winter. My truck never saw 18mpg, never, not even on one hour drives on the interstate, but now I have seen as high as 19.8. No boat tail installed, no engine change, no drafting, no structure behind, no axisymmetric flow, no speed change, only VG's placed at appropriate spacing at 30 degree angles and 2 extra days of driving before refueling.
But thanks for the input. Just trying to pull out the extra mileage on each tank like everyone else here.
