The mileage figures posted for the 2009 Challenger are as follows:

3.5L= 18/25 mpg

5.7L (Auto)= 16/23 mpg

5.7L (Manual)= 15/23 mpg

6.1L (Auto)= 13/18 mpg (This is for the Dodge Charger. Have not yet seen the Challenger mileage posted).

The bottom line is that the 6.1L will be subject to the gas guzzler tax. The 5.7L will be okay, but it remains to be seen if the 5.7L (Manual) will be affected.