i recently read an article in a 4x4 mag where they swapped gears 3.55 to 4.56 and claimed they got better gas mileage on highway driving. i am not sure what tires they had but could someone explain how this happens. it also stated that the gears reduced the tranny temp. i think this is because of the mechanical advantage correct? but wouldnt the 4.56 cause higher rpms at highway speed and thus increased gas mileage.

 

Yes the motor will be running at higher rpms but it will require less work to maintain speed. That's how the gas mileage improves the motor isnt straining itself

 

The concept is easy to understand, if you get on a bicycle and ride in too high of a gear. You rpm will be low, your legs will get tired much sooner, and after some time you'll develop some nasty pain in your knees. Now, drop to a lower gear on your bike, and your rpm will increase, you will be able to bike further, and your knees will be healthy.

 

thats a great way to put it!