On average my trip meter is around 400 when I put fuel in, but I don't always fill it up (depends on fuel price etc) so would estimate I use 400 to 450 a tank, car is stock 2002 tj no mods, city driving nothing over 60kph. Highway driving, again depending on conditions (head winds and overtaking) I get an easy 600+. Best ever distance I ever got was deer park in melb to the Mobil at the bottom of the freeway in Adelaide on one tank. Was somewhere around 700kms on one tank. But have never been able to replicate that.