Why Oil Changes Are So Important

February 3rd, 2016

You probably heard it from your dad years ago – “the best way to get the most miles out of your car is to get the oil changed regularly.”Oil Changes in Murfreesboro TN

Well, your dad was right, and it’s still true.

The internal combustion engine generates a lot of heat, due to the friction between moving parts and the thousands of tiny explosions that occur in the cylinders. Something has to disperse that heat and cut friction, and that “something” is your engine’s motor oil. The clearances between bearings and rods or cranks, or between pistons and cylinder walls, are microscopically tiny. Without the protection of motor oil, the friction from those parts would soon cause them to overheat to a point where they actually weld to each other and seize the engine.

The explosions in the cylinders, however, also generate a lot of carbon, acids and other contaminants that make their way into the oil. Water vapor also accumulates inside the crankcase; during short trips where the engine never warms up to operating temperature, the water vapor won’t ever burn off and will contaminate motor oil. Oil has detergents and dispersants that are designed to suspend carbon and other particles so that they can be trapped in the paper element of the oil filter as the oil circulates. Eventually the filter becomes contaminated, though, and carbon can start to accumulate as a sludgy buildup on internal engine assemblies.

For years, quick-lube shops and oil companies pushed the “3,000 mile” rule for oil change intervals. With today’s motor oil formulations, it’s generally agreed that a 3,000 mile oil change is a bit of overkill. Conventional mineral-based motor oil can be changed at a 5-7,000 mile interval with no harm to the engine. Manufacturers now consider conventional oil to be obsolete, and recommend synthetic oil for all new vehicles. Synthetic oil flows better at cold temperatures, doesn’t thin out at extreme heat, and generally does a better job of engine protection as compared to conventional oil. Synthetics are more expensive per quart, but the oil change interval with synthetics can be stretched to about 10-12,000 miles (always check owner’s manual for manufacturer’s recommendations).

So how long has it been since your last oil change? Can’t remember? Check the condition of your oil on the dipstick for an easy rule of thumb. Clean motor oil should be amber or honey-colored, and completely translucent. Darker brownish oil that’s still translucent will need to be changed soon, while oil that’s the color of black coffee and has a sour or gasoline-heavy odor to it is definitely in need of a change.

Whether you drive an older model or a brand-new ride…and whether you prefer conventional mineral-based oil or synthetic…we’ve got you covered at American Tire Company in Murfreesboro, TN. Set up an appointment with us for your next oil change, and we’ll get your car taken care of quickly so you can get back down the road again! 

  Posted in: Auto Repair 101