The Secret of an Oil Change

Find out what regular oil changes do for your car.

“Oil doesn’t just lubricate—it’s the garbage disposal for the engine,” says mechanical and engine expert Mike Arman. “Oil gets contaminated with metallic particles from normal wear in the engine, and carbon and ash from burned oil.”

Then there are byproducts created by the water from exhaust. “It doesn’t all go out the tailpipe,” Arman says. “Some goes down past the rings and into the oil. There, it combines with sulfur in the oil to make diluted sulfuric acid.”

As a product, motor oil is approximately 85 percent oil and 15 percent additives, such as detergent and anti-foaming stabilizers that break down over time due to these contaminants. That’s why oil changes are necessary.

“Think of mopping the floor with a bucket of water and detergent,” says John Wesley, CEO of Universal Lubricants, a recycled oil manufacturer. “The water starts out clean and gets the job done, but the more you use it, the filthier the water becomes. Without changing the water, eventually you’ll be doing more harm than good with your mopping, making the floor dirtier and dirtier.”

When Do You Need an Oil Change?
It really is critical to change your oil on a routine basis. But what’s “routine”? It’s different for every vehicle.

Every 3,000 miles is not the rule anymore. Vehicles are much more advanced now. “The number may be 3,000, 5,000 or even 7,500 miles,” says Champe Granger, owner and operator of Grease Monkey franchises in Richmond, Va. “You should change your oil as often as it’s recommended in your owner’s manual. Also, some vehicles have oil sensors to guide you.”

That said, consider a shorter-than-normal interval if you have a long trip coming up, especially since many shops will check belts and hoses, fill tires and top off fluids during the appointment.

In the end, it’s about paying less—not more. “It’s human nature to try to stretch it,” Granger says. “But an oil change is $50. An engine replacement is $3,000.”

Here to Help Before you find yourself on the side of the road, learn more about Nationwide Roadside Assistance and talk to your agent about how it can help you.