Well we just got back from doing a round trip from Reno to Oakland. We filled up 12.24 gallons and arrived back with 450 miles. That sums it up to being about 36 mpg. We never did over 70 mph and cruised around 65 mph. This coming from a 2004 Chevrolet Malibu Classic (with the ecotec 2.2L engine) You did not say the year or size of the engine which would be helpful.
The EPA mileage estimate for the 2004 Chevrolet Malibu is 21 mpg in the city, 31 mpg on the highway.
The EPA mileage estimate for the 2006 Chevrolet Malibu is 20 mpg in the city, 29 mpg on the highway.
The EPA mileage estimate for the 2011 Chevrolet Malibu is 22 mpg in the city, 33 mpg on the highway.
The EPA mileage estimate for the 2008 Chevrolet Malibu is 22 mpg in the city, 30 mpg on the highway.
The EPA mileage estimate for the 2001 Chevrolet Malibu is 18 mpg in the city, 26 mpg on the highway.
The EPA mileage estimate for the 2007 Chevrolet Malibu is 21 mpg in the city, 31 mpg on the highway.
The EPA mileage estimate for the 2012 Chevrolet Malibu is 22 mpg in the city, 33 mpg on the highway.
The EPA mileage estimate for the 2013 Chevrolet Malibu is 22 mpg in the city, 34 mpg on the highway.
The EPA mileage estimate for the 2002 Chevrolet Malibu is 18 mpg in the city, 26 mpg on the highway.
The EPA mileage estimate for the 2003 Chevrolet Malibu is 18 mpg in the city, 26 mpg on the highway.
The EPA mileage estimate for the 2010 Chevrolet Malibu is 22 mpg in the city, 30 mpg on the highway.
The EPA mileage estimate for the 2014 Chevrolet Malibu is 25 mpg in the city, 36 mpg on the highway.