Over 625 miles a tyre with an A rating will use over six litres less fuel that with a G rating, meaning that over the lifetime of a tyre, usually around 10,000 miles you could save more than enough in fuel savings to buy your next tyre at Easywheels.co.uk. It's also said that up to 20% of a cars fuel consumption is down to the tyre and it's rolling resistance, so spending slightly more upfront could see you yield the benefits down the line.