You have lots of choices when it comes to pumping gas into your vehicle. You can go to a national gas station that advertises widely, or go to a local discount station to save a few pennies a gallon. At every station, you can buy different grades of fuel. Gas retailers try to differentiate their gas from that of their competitors through marketing and advertising campaigns that suggest their blend is better. As gasoline continues to increase in price due to tension in the Middle East and the weakening dollar, saving money on gas is more important than ever. Some people choose the cheapest gas they can and will drive across town to find it. Others only allow premier grades of gasoline to touch their tanks. Is there really difference?
In the United States, the U.S. Environmental Protection Agency (EPA) regulates the composition of gasoline that goes in your vehicle. It sets quality standards along with minimum and maximum levels of additives and fluorocarbons. All gasoline sold in the U.S. meets these standards, including the gas sold at discount gas stations. The main difference between cheap gas and its pricier counterpart is the level of detergents added. A minimum level of detergents is required by the EPA to be present in all retail gasoline. Some national gas retailers have higher than minimum levels of detergents which are better for your vehicle and may prolong the life of the engine. Detergents prevent residue buildup from occurring. When significant buildup is present, your vehicle needs to burn more gas and the engine and valves work less efficiently. It can cost you more money in the long run. Although putting discount gas in your vehicle every now and then is not likely to result in long-term residue buildup, you may be better off buying higher-detergent gas on a regular basis so the residue doesn't build up in your gas tank. You also should keep in mind that you are burning fuel by driving across town for the cheapest gas, and you may be spending more than the savings you find. There are several independent studies online to help guide you to the gas that is right for you.
Gasoline comes in three grades at most gas stations: regular unleaded and two higher-octane grades. Unleaded is an unnecessary component in the title because lead has been removed from all gasoline in the U.S. since 1996 in order to reduce toxic pollution. Regular grade gas is a minimum of 87 octane, which refers to the compression ratio of fuel in the engine cylinder. Gasoline can spontaneously ignite when compressed, which causes that familiar knocking sound that can damage engines. The higher the octane in the gasoline, the more compression it can take before ignition. In the 1980s and prior, vehicles were far more susceptible to this type of ignition and octane made more of a difference than it does now. Today's engines are fuel-injected, which eradicates most of the problem. The majority of vehicles are designed to run on 87 octane fuel. Some higher-end luxury vehicles, however, were designed to operate on premium grade fuels. In order to not violate the warranty and to keep your vehicle running properly, always use the grade of fuel called for in the vehicle's owner's manual.
The Bottom Line
Gasoline is an expensive commodity across the country. Although all gasolines meet minimum federal guidelines, some are better for your vehicle than others. It is not wise to try to save a few pennies at the expense of your engine, but there is no need to buy premium grade gasoline if your vehicle is built for regular.
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