Planned top off?

[otis24]

So, here is a thought. A Mobil 1 study that I read suggested that as little as a half quart of top off oil rejuvenates and adds life to oil, making it possible to do extended drains. In the case of that study, they did an 18000 mile OCI. Fresh oil filters played a part as well. What if you have an automobile that does not use/consume oil? For those of us who have Fumoto Valves or pumps, is there any wisdom to draining a quart of oil and adding a fresh quart to extend the drain interval? I would say in most OCI scenarios, it wouldn't be needed. But deliberately changing a quart of oil is "cheap insurance" and gives one peace of mind. In my case, I am debating whether or not to do one year OCI's. I would average about 6k miles per year. I live in a cold climate and short trips are certain. Drianing off a quart and adding a fresh quart would certainly be a cheap way to enhance the current fill if extending the OCI to one year. Your thoughts?

 

[SwampSurvivor]

I am on a 10K run right now. I used a Supertech filter and changed it out at 5000 miles. Lost about 1/2 quart of oil and topped it off.

 

[Blueskies123]

If you are only driving 6000 miles a year with short trips in cold weather I would just use a quality synthetic and change it with the filter once a year. Cars and oil are made so well these days I would worry about other things.

 

[sir1900]

I suppose that depends on the application in which the oil is being used. For some engines, such as many Nissan VQs, I would say a full oil change would make more sense seeing how hard these engines are on oil.

 

[paulri]

Was it this study? http://www.brianschreurs.org/neptune.spacebears.com/cars/stories/mobil1.html

If so, that was a lot more than a half quart, across the 18,000 miles. And it was only one vehicle.

 

[otis24]

Yes. It was that study. My point was that as little as a half quart rejuvenates the oil, but not for 18k miles. For a 6k-10k mile OCI, one quart of topoff oil should be more than sufficient. Particularly if one has doubts or concerns about their best oil choice holding up over time.

 

[WobblyElvis]

Sometimes I do exactly that. Drain some of the oil and top it up to extend and oil change. Because of the weather situation, I change oil in the spring and fall. Don't like to work in the snow. I haven't driven the car much this winter and the oil should still be good for another couple of months. I may drain half the oil and top it up. This will take me to the next oil change in OCT/November. Maybe I economise to much!

 

[Whimsey]

With my 1996 Zetec on a previous OCI of almost 9,000 miles of PP 5W-30 with not adding any oil during the OCI, it barely dropped below the full mark, my UOA came back with low metal wear and still plenty of useful TBN. But every vehicle is different, I'm just lucky with this one, it doesn't really use any oil, even in long OCI's and the UOA's are real good at those mileages. My wife's new 2017 Explorer with the 2.3L DI, twin turbo might be a totally different beast, we'll find out.

Whimsey

 

[Kuato]

Interesting thought; this would be an inexact science though, and very dependent on engine and driving habits. Question is: how much time and effort are you willing to put into the research?