So, Why Use Synthetic Motor Oil?
As mentioned in a previous post, synthetic motor oils have a higher molecular stability, so they are able to serve for a longer duty cycle – in some cases, 15,000 miles, or 1 year. If your vehicle goes from an oil change every 5,000 miles to one every 15,000 miles, you are generating 1/3 the amount of used motor oil to be dealt with and also cutting the amount of time you spend changing, or waiting for your oil to be changed, by 2/3. While the appropriate oil and filters to go 3 times as long may cost more than conventional oil and standard filters, they do not cost 3 times as much, perhaps not even double. Also keep in mind that, as one of the major functions of motor oil is to keep your engine clean, you must change it (even synthetic) when it is dirty, so you may not get 3 times the duty cycle – your mileage may vary.
Another compelling argument for using synthetics is that they do a better job than conventional oils with respect to lubricating an engine at startup, when most engine wear occurs. The specifics behind how synthetics do this, and how they are different from conventional oils will be the topic of our next post.