Let’s Talk Oil Changes
For years, it’s been an article of faith that oil changes are the best way to get the most miles out of your engine. But why is that true? Why are oil changes so important?
An automobile engine is designed and assembled to extremely tight tolerances. The tight fit between moving parts means that a great deal of friction is created; motor oil is the film of lubrication that helps cut the wear created by friction and helps disperse heat. Without oil, parts like pistons and bearings would soon overheat to a point where they will actually fuse to each other, seizing the engine.
Inside the cylinders, the spark plugs set off explosions of a fuel/air mixture, generating power. Those explosions also create a lot of byproducts like carbon, acids and other chemicals. Along with tiny metal shavings from moving parts, these contaminants will start to dirty up the engine’s oil. Motor oil contains detergents and other additives that will suspend contaminants so that they can be trapped in the oil filter as the oil circulates. Over time, though, the filter’s paper element will become saturated and carbon will start to build up as sludgy deposits on bearings, valve components, and other parts. If motor oil is left for this long, it’s essentially lost its lubricating properties and engine wear will soon start to accelerate.
For quite a long time, manufacturers and oil companies recommended a 3,000-mile interval between oil changes. Just as cars have advanced in the last 20 years, though, so has motor oil. Newer formulations of conventional oil can easily go 5,000 miles between changes with no significant sludge buildup.
Synthetic Oil – Is It Worth It?
You have undoubtedly seen the TV commercials for synthetic motor oil, and might be wondering if it’s really that superior to conventional oil. The answer: an unconditional yes.
Synthetic oil has several real advantages:
Even the most carefully refined conventional oil has impurities like paraffin and salts. Synthetic oil, developed entirely in a laboratory, is much more pure.
Synthetic oil is more stable and uniform at the molecular level. That means increased “shear strength” – the shear point is the point at which oil is squeezed completely out from between two surfaces.
Conventional oil tends to thicken at low temperatures and thin out when subjected to extreme heat. Synthetic oil retains the same flow properties across a wide range of temperatures, doing a better job of protecting the engine in extreme hot or cold weather.
Turbochargers spin at extremely high speeds, often over 200,000 rpms. That means they generate tremendous heat, and synthetic motor oils get to the moving parts of a turbocharger faster and better.
While synthetic motor oils are about twice as expensive per quart, their superior lubricating properties make them worth it. It’s also worth noting that synthetics can easily go 7,000-12,000 miles between oil changes (or more), offsetting the added per quart cost.
Synthetics are now the preferred motor oil for just about every manufacturer’s new cars. While earlier formulations of synthetic oil were reputed to cause engine seals and gaskets to degrade and leak, this isn’t really a problem anymore. Even an older car with 200,000 miles on it can benefit from the enhanced protection of synthetic motor oil.
At New England Tire Car Care Center in Attleboro, MA, we do a lot of oil changes. We also see a lot of cars with high mileage on the odometer and really clean, tight engines thanks to a regular oil change schedule. What’s your odometer say? Make an appointment with us for an oil change soon!
|Let’s Talk Oil Changes was written by Parker Ashton of New England Tire|