These four automakers decided to do something about this problem and create their own class of gasoline called 'Top Tier Detergent Gasoline', containing a higher level of detergents. This was meant to keep vehicle owners happier with better engine performance and wear and allow gasoline marketers the opportunity to distinguish their product from the competition.

In 1994 a few gasoline distributors adopted this new industry standard and since then it has expanded across North America. Current retailers are QuikTrip, Chevron, Conoco, Phillips, 76, Shell, Entec Stations, MFA Oil Company, Kwik Trip/Kwik Star, The Somerset Refinery, Chevron-Canada, Aloha Petroleum, Tri-Par Oil Company, Shell-Canada, Texaco, Petro-Canada and Sunoco-Canada.

I personally discovered this gas by trying the 'silver' gas out at Shell. I thought it would just increase performance for this one fillup due to the higher octane. Surprisingly, later fillups with the cheaper bronze gasoline still saw a 5% increase in mileage, not bad for an aging 5 year old car.

This gasoline is good for new cars as it keeps the engine running optimally and especially good for older cars with engine deposits.

zone-car.com