We took the benz from Lexington Ky to El paso and back on I44/I40 in May, averaged 77 MPH and got a 27 MPG both ways burning hi Test. While in the Mountains 65-70 MPH we got 25 MPG running mid grade fuel above 4K feet altitude. Temps the whole week were between 88 & 97 Deg F ;/ the climate control was alaways on.

200K miles+ on the odometer.

This exceeds MFG mileage of 24 HWY/19 City