I don't think 4.10 or 3.73 would kill your mileage... Sure, you're running more rpms, but you also have the throttle open less. Less air in = less fuel needed. You may or may not see a decrease. Your right foot is going tobe the deciding factorhowgood yourfuelmileage is.

 

This is EXACTLY what I thought.
I'm sure my hour trip to my dad's would be bad on gas mileage, but other than that I'm almost 100% city driving.
I really wanted the higher gears to feel what my cars got in the seat of my pants, lol.
I blew the doors off a v6 Mustang nub, and coming out of the hole that much faster was an awesome feeling, thus, I want more, lol.

 

lets be honest is gonna be easy to keep your foot out of it when its faster?

 

Of course not!
But its not like I don't do that now as it is...lol
So I see it, really no change in mileage other than a twice a month highway drive.
Any other objections?

 

if you dont stay off it your gonna take a bigger hit on milage with the big gearing but im doing 3:42s here soon so who am i telling lol'

 

might wanna think about getting it programmed for the 4.10's so the mileage on the odometer will be right, otherwise i think it'll show higher than actual miles.

 

Yeah, would definately need it lol.
Probably would throw in a stall and a tune at the same time.
Might as well ask this for excuse of a bump:
Best place/company to buy gears?