Ok...

Just trying to find out what is myth and what is true. I was doin a little math and I realized that an M6 with 4.56 gears has the exact same cruise RPM as an Auto with STOCK 3.23 gears. So wouldnt that mean that it would get very similar gas mileage if not BETTER?

So many people claim that when you get new gears, it makes the gas mileage go down alot. I know in an Auto with 3.73s, the cruise RPM at 75 is almost 3k, but in an M6, there is alot of room for gearing.

Anyone on here run anything over 4.10s and does anyone sell 4.56 gears for a 10 bolt?

 

I'm running a 4.56 gear in my Impala SS. I love em. I can cruise at a lil less than 3k at 80mph. I still get pretty good mileage even though its a 4800 pound car. I actually got almost 2mpg when I went from my 3.08's to the 3.73's back when it had an auto. But thats a whole different animal from the f-body.

 

are you on a 10 bolt and where did you get them?