Based on the 3.73's, I'm guessing you are referring to the 2010's, so I'm not 100% on those, but I can give you my experience for the 2008's. I had the 3.55's, and I got as high as 30 MPG highway on a 280 mile trip going 70-75 mph. Around town would be 15-17 depending on driving style (sometimes...