It was very economic in highway... if you drive slowly (say at 55 mph), you can get even close to 28 mpg, unbelievable... I usually get around 22 in highway, because I drive at 70 and 75 mph. When I go really fast, it comes down to 20 mpg. In city, it depends, average I would say would be aroune 16, 17 which is not bad for a big car as a Cadillac.
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