GORV - Digital Magazine Issue #29 | Page 38

distance to empty.  It’s a useful feature when in remote areas, with large distances between fuel stops.  We actually found this to be surprisingly accurate most of the time. The last method we used was to calculate the fuel economy manually at each fill of the tank. This is by far the most accurate way of assessing fuel economy. However, there is one point I need to make here:  Fitting the larger tyres affected the accuracy of our odometer by a factor of five per cent. We were actually travelling longer distances than indicated by the odometer. We just had to remember to include this in our calculations. On a good day, Marty's Cruiser will use 17L/100km of diesel. 38 \ The other issue with this method is the variety of fuel, fuel pumps, as well as a number of other factors that mean you never really get a consistent measure at each refill. ‘Hi-flow’ diesel pumps can create a lot of foam in the fuel, meaning you don’t quite fill up as much as you might at a low-flow pump. Truck diesel also foams a lot more than the higher quality premium diesel. Higher temperatures can also affect the amount of fuel you can squeeze into the tank.  All together, the difference could be anywhere between five and seven litres per fill.