delete

 

no need to be ashamed, that's what we're here for. the fuel that the engine consumes is controlled by the torque demand. when going to bigger tires, you're going to have to bury your foot a little deeper to get the same acceleration as before since you are now at a torque DISadvantage, but that means more torque is needed from the engine=more fuel. gears will even the torque back out to what it was before so putting your foot down a certain amount gives the same aceleration as before.

gears alone will not gain you much for mpg, but if you lost city mpg with bigger tires, the gears will get you back your city mileage. if you gained some highway miles with the tires, gears might cost you a little bit on the highway. if you do it right, you'll go back to the mpg you were at before tires.
hope i answered what you were asking, and hope this posts

 

I went up to 37" tires and still had stock gears. My rpms were at 1700 when crusing at 70 on the highway. Once I regeared to 4:56 gears my rpms only went up to 2000 at 70 mph. That is not a sig. amount! But it makes a bigger deal with torque and power! My overall MPG went up from 12.5 to 13.17. Not a huge amount, but what a difference it made with low end torque and power!

 

 

Sorry for the "in your face print" above, but I had to U/L my post as a .jpg to get it to take. Got sick and tired of trying to type and get it to "take"!!![:@][:@][:@][:@][:@][:@][:@][:@][:@]