Changing the rear gears
Just a thought...
I drive 105 miles to work everyday and 105 from work everyday. If I do the speed limits 65 and 55 then I can average 30mpg's according to my display (which I believe is fairly accurate given how much I pay to fill it up every other day). I just bought a cheap a$$ CAI off eBay for lilke... $65 to see if I want to invest in an Injen or Volant. It would be nice to see a 2-4mpg gain as that equates to several hundred dollars over the course of a year.
So my question is... has anyone tried changing the rear gears to maybe step down the RPMs while cruising on the highway? I don't really care about performance as that doesn't help me at all given the amount of highway driving I do. Any info would be cool.
FYI, my car is a stock 2006 G6 GT 3500 with 155,000.