Mate,I also don't know if you're going to average 10km per litre towing a van.I know that this isn't what your thread is really about but if you manage 6km/l you should be thrilled.I've done extensive towing,including Brisbane to Darwin each year with a big tinnie, 2 adults and bugger all in the car and have never done better than around 6km/l.That was twice with a supercharged S and 8 times with a stock V6 Exec.That aside.I agree with everyone else that the LSD is a good way to go cos I can't believe that they haven't been stock in all rwd cars for the past 20 years.Enjoy your trip.