Cruise control can make a difference as well. We find the Commodore can be quite efficient when we can just sit on 100kph, if we are stuck behind someone who can't decide if they are doing 90 or 105, the fuel gets chewed up. We are noticing it with the new Swift, it does not have cruise control, whilst the Colt did. With about 3/4 of DH's driving being at 100kph, is makes a significant difference.