How Often Should I Change My Oil?

8. February, 2018


I am asked ” how often should I change my oil? ” often.  The answer to that question will vary with different resources.  The industry standard from a shop viewpoint is 3,000 miles or 3 months.  I change the oil on my personal vehicles every 3,000 miles and that is what I tell my customers.  Of course the customer always has the last say in what guidelines to follow.  I am not a scientist, I just know what I have seen with varying intervals.  I researched this topic a little bit and this is what I found.

Consumer Reports suggests 7,500 miles.  I would advise customers to use that interval if using a synthetic oil.  Synthetics have completely different characteristics, which would be a different subject to be covered in another post.

Advance Auto Parts has an article that really doesn’t give an answer, but illustrates how over time contaminants will turn your oil dark, and that you want clean oil lubricating your engine, not grit and contaminants.  Contaminants will turn your oil to sludge.

I found an article on Angie’s List that adds another thought to the mix.  One source in the article said “Having an oil change more often means that your mechanic is checking your vehicle three or four times a year rather than twice a year,”  as well as “Five thousand miles on the highway in five months is better that 1,500 miles of in-town driving in five months.”  I agree that driving habits and conditions will have an affect on the life of your oil.

AAA emphasizes that meeting the manufacturer guidelines for the proper oil type and viscosity is the most important concern.  The article also mentions driving conditions. indicates that anybody recommending 3,000 miles is just trying to make money.  I find that absurd, oil changes are a money loser for most repair facilities.  Many shops use oil changes as a loss leader and will upsell you on everything they can find.  Of course it is the responsibility of the shop to keep you advised if you have any real concerns, but upselling is a real issue for the consumer.  So many repair shops prey on the consumer in this situation.  It is like when I go to the dentist, I have to rely on them to tell me what concerns I have without selling me a bill of goods.  I have no idea if what they are telling me is true, I have to trust them.   I dislike that my industry has become so shady, but again, this is a topic for another post.

Firestone Has a very good article about what creates sludge and how diving condition and climate affect oil.  It is good information.  The article does challenge the 3,ooo mile rule of thumb however.

My conclusion after reading these articles is that most information is stating that 3,000 mile intervals is more than necessary.  After reviewing this topic I will be advising my customers what I have learned and letting them make their own decisions.  Am I going to change my oil change intervals to 5,ooo or 7,500?  That is not likely.  Having been in this business for over 40 years now, I have seen a lot, and I have seen what oil looks like after 7,500 miles.  My customers can make their own decision however, I will advise them what their manufacturer recommends and tell them what I do.  As I said, I am not a scientist, I just know what I have seen.

The most important thing is to monitor your oil level.  Cars can definitely use oil, sometimes a lot of oil.  I have seen factory representatives tell car owners that using a quart of oil in 800 miles is acceptable by manufacturer guidelines. It is your responsibility to monitor your oil level between oil changes.  I would not expect a car to go 7,500 miles without having to add oil.