MPG reading in imperial gallons
 

My UK Tucson has miles per gallon calculator in US gallons. Is there a software mod available to convert it to imperial/UK gallons. Seems a bit dumb they did not work it out at the factory. The difficult bit was moving the steering wheel to the other side, software mod should have been free. Also, diesel consumption is quite high- about 30 mpg, but improves dramatically in very warm weather. Is there something wrong?