I tow a vintage caravan behind a stock FE. It okay if you're not in a hurry. I cruise at 80-85 until I get to a hill; then take what I can get. I recently did 3200 k mainly up the Hume and Pacific highways and averaged about 200 k to a tank full. The van weighs in at around 950 kg fully loaded. A friend of mine with an FB gets slightly better fuel consumption with his smaller van.