Here are some gas mileage records from my receipts:
(04 XF 6 spd, 33K miles, no commuting, minimal stop and go, A/C only when needed, upshift asap, lots of 45-65 mph driving, basically granny driven)


408.1 miles 14.5 gallons 28.14 mpg


325.8 miles 10 gallons 32.58 mpg


387.9 miles 13.5 gallons 28.73 mpg


431.5 miles 14 gallons 30.82 mpg


213.2 miles 6.58 gallons 32.4 mpg


418 miles 14 gallons 29.85 mpg


403.6 miles 14 gallons 28.8 mpg


424.3 miles 14.07 gallons 30.15 mpg