How Safe Are Extended Oil Change Drain Intervals?


With oil drain intervals fluctuating from low as 3,000 miles all the way up to 25,000 miles it’s easy to get confused. Then throw in the normal and severe conditions it’s very easy to get conflicting information.

It is becoming more and more common for both oil and car manufacturers to suggest going well beyond the old 3,000 mile drain interval that used to be considered good practice. People are always skeptical of change however, especially when the information is so very conflicting. How is one to know who is right? Let’s take a look at the facts so that you can decide for yourself.

Why We Change Motor Oil

It would help to understand why we change motor oil at all. Motor oil is responsible for several things including lubricating critical engine parts and to a certain extent, cooling the motor. There are numerous things going on inside your engine that deplete your additive package. Constant exposure to moisture can shorten the life of your oil and begins to diminish the actual time in service. Thus motor oil can be “worn out”, so to speak.

How Oil Manufacturers Decide How Often The Oil Should Be Changed

The most logical, and most honest way to determine how often motor oil should be changed should be based on the oil’s ability to do its job: condition the seals and lubricate the engine. One company in particular suggests drain intervals of 25,000 miles. That means this oil can resist the day to day punishment and still effectively lubricate critical engine parts and provide the additives to keep your seals healthy for at least that long.

How Oil Manufacturers Make Extra Money

There are some companies, however, who seem to take a less scrupulous and more money grubbing approach at dictating drain intervals. Some of the major brands that offer 15,000 miles drain intervals suggest changing the motor oil at the manufacturer’s suggested intervals until the car is no longer covered by a warranty. After your warranty is expired some oil companies recommend going the full 15,000 miles. This is rather silly, and no mechanic in his right mind would tell you that your oil drain intervals should increase as your car gets older. If anything, the drain intervals should be shorter on older vehicles, assuming that inferior or questionable motor oil was used at some point. If it’s okay to go 15,000 miles after the car has 36,000, 60,000, or even 100,000 miles on it, it stands to reason that those same drain intervals would be suitable from the time your car is brand new and still under warranty.

It’s Federal Law as dictated by the Magnusson Moss Act for the car manufacturer to void your warranty for using oil with longer drain intervals unless they provide both the oil and the labor to change it, free of charge, so the warranty is not at issue. If the motor oil is capable of protecting your car for longer, than your car does not benefit from changing it more often. You, who has to pay for the oil, certainly do not benefit from spending more money. Oil manufacturers are in business to turn a profit and any way they can they will. Their oil change recommendations are geared towards maximizing profits and keep you coming back as often as possible.

There is nothing stopping you from going well past 3,000 miles on any motor oil that offers extended drain intervals right from the beginning. Or, if you’re really looking to save some money, you could go with the oil that recommends 25,000 mile intervals, regardless of the vehicle’s mileage and warranty status.


Source by Steve Tarini