I have an Edge. It gets seems to get better milage on the high setting but I might try that. Unfortunantly I'm back to work so I use the conpany truck. Maybe I should put the unit on the company truck, as it only gets around 12mpg.

I can see that the added size of a hydrogen cell may be the ticket but the more you spend the less likely you will get the payback for sometime.
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2006 Ram 2500, SB, 4X4, Auto, Edge, 5" home made air tube, Magdrive HHO, stock exhaust.