Motor oil is a key lubricant used in all automobiles that keeps the moving parts of your engine running smoothly. Did you know that oil also cools the engine and acts as a sealant? Most oil products are a mixture of synthetic chemicals and a liquid derived from petroleum, which is also used in the production of gasoline. Other offerings are fully synthetic and these have been shown in laboratory tests to operate at the highest level over the greatest variance of temperatures. Most premium oils contain detergent, which helps break down some of the gunk that builds up inside of your engine. When you change your oil, you are effectively cleaning the inside of your engine.
Oil helps prevent corrosion on the inside of your engine by trapping water particles and acid. These particles turn the oil black and also make it thinner. Even though synthetic oil does not break down like regular oil does, it is still important to change the oil regularly to get rid of the particles in the oil and solids trapped in the oil filter. A premium oil filter is an inexpensive way to enhance your engine life, especially if you push your oil changes beyond the traditional 3,000 mile interval.
When you buy oil, you will notice that it is labeled 10W-40 or 5W-30, etc. The first portion of this number tells you how viscous (thick) the oil is at low temperatures and the second portion tells you how viscous the oil is at high temperatures. Drivers in cold climates often use oil with lower first numbers to enhance oil flow at cold startup. Your best bet is to use the oil recommended by your owners manual.
Many dealerships and mechanics will offer oil changes at cost or even at a loss to get customers in and then try to upsell them on additional (and more profitable) repairs. Although you can get your oil changed cheaply by someone else, doing it yourself provides numerous benefits. You ensure that the job is done correctly and you can use premium oil and premium oil filters (strongly recommended). Many cars have aluminum oil pans - if a mechanic uses an air gun to put the drain plug back in (they almost all do), it will likely strip the pan and now you have an oil leak. Think about it this way, your engine operates at temperatures in excess of 4,500 degrees Fahrenheit and oil is the only thing preventing it from becoming on molten chunk of metal. Do you really want to rely on someone else for this? Thinking about changing your own oil, but don't know where to take the used oil? Most auto parts stores will dispose of used oil for free.