Originally Posted by Mr. Wyndham
I think that's because the ATS is geared and wears tires for performance in the 3.6L trim...the Camaro, in contrast, is geared for and shod in fuel economy tires.
With a similar treatment...I wonder if the ATS 3.6 wouldn't get 31-32mpg...
Actually, the final drive ratio is the same between the two if my memory is correct (3.27) so I too am a bit surprised the ATS does not have a small MPG advantage. Only the 2LS Camaro has highway MPG rating of 30 because it has a 2.92 final drive ratio. Other V6 Camaros are rated at 28 MPG.
I wonder if there is something else affecting mileage for the ATS, or if the weight loss really doesn't help mileage much?