Drivers with certain cars will be forced to use 'premium' fuel in huge change later this year A MAJOR change to petrol could see certain drivers forced to use 'premium' fuel instead of regular unleaded later this year. Over the summer, the standard unleaded petrol supplied through the pumps will change from E5 fuel to a new formula called E10, designed to reduce emissions. But the new fuel, which will not affect diesel owners, will not be compatible with all cars and vehicles as the Government has warned. In those situations, some cars over the age of ten will need to use the more costly 'super' grade, also known as premium fuel, instead.