Originally Posted by PaleMelanesian
So THAT is what a tall 6th gear will do. Wow! ~10 mpg better than my Fit all the way across.
What rpm do you run at 60 mph? I'm at 2800.
Not bad for a large-ish compact sedan that weighs 3000 lbs. If I remember right, it's reving almost right at 1500 @ 50 MPH, so at 60 it would rev about 1800 or so. It's a .61 6th gear with a 3.83 final drive and a 26.3" tall tire (215/55-17). No doubt a 6th gear in the Fit would pay off big time.
5th in the Eco is the same .74 ratio as the regular Cruze's 6th gear. That super tall .61 6th is probably responsible for 75% of the mileage increase over the standard car. With my Saturn I was always wishing for a taller gear, but not with this car.
There are a couple of 6 spd manual transmission options from some GM European diesel cars that have even taller gearing. I'm sure putting even taller gears in would suck a lot of the fun factor out of the car, but I drive for economy. Getting a transmission from Europe could be expensive, though!