Long term oil changes

[FCD]

So, if you drove a car with fresh oil 500 miles, parked it in 1970 outside in Minnesota, returned to it in 2023, the oil would be as you left it in 1970 (assuming no leaks, no tampering)? Or are you speaking less literally and more figuratively e.g. in a short-term of 2 years oil won't degrade to unsafe levels?

Sincerely curious about the answer. Not trolling here, genuinely curious since I live in a small walkable town with 2 vehicles in a similar low-use profile. If I can learn something, and change the oil less frequently, it might be my new COA.

The difference from 2 years to 50+ is quite a bit, ofcourse in 50 years the oil won't be any good anymore as inevitably a lot of moisture will have gotten inside the engine and the additives will probably fall out from the oil.

 

[4WD]

So you agree, you are not an expert.

Yeah, but called you hoss … better chill man

 

[Fahrvergnügen]

So you agree, you are not an expert.

What certifies you as an oil expert?

 

[ATex7239]

I am in the one year camp. I had a Dodge truck years ago that I put only a couple thousand miles on per year. Always did an annual change every spring with Mobil1 and a TG filter. I spent more money keeping the inspection and registration up than I did on the oil change.

What are we talking here? $30-ish a year? I wouldn’t necessarily call it “a waste.”

 

[kschachn]

Hyperbole aside it’s good to remember we are talking about two years here per the OP, not 53.

 

[Greasymechtech]

Answered simply with a UOA

You run it for a year, grab a UOA with tbn/tan/nitration/oxidation.... and guestimate if you want to go another year

I don't care for cellulose with extended time. It breaks down with age.

Moisture is there regardless if you're taking long trips or not.

 

[leadcounsel]

Hyperbole aside it’s good to remember we are talking about two years here per the OP, not 53.

But you said it does not go bad and does not degrade. 50 years was used to illustrate a point. Intentionally. I'm a literal person. Perhaps your incorrect uses of absolute terms was implied, or just clumsy. I'll give the benefit of doubt it was just flippant terminology.

But now we agree that clearly it does go bad, does get contaminated from sitting, and does degrade. Now that we agree that it goes bad and degrades, the key is to determine at what point. Is it at 40 years? 30 years? 5 years? 1 year? While you are quite likely correct that in 1 or 2 years it probably does not go bad from sitting, at what point does it go bad. "Never" or "Does not degrade" is the wrong answer on a forum that is meant to be more technical in nature. It would be similar to a lawyer speaking in incorrect technical absolutes on a legal forum. It would be ill-information. Further such absolute terms totally contrary to known accepted industry standards and recommendations would undermine that attorney's credibility IMO.

According to every owners manual for every vehicle I've ever owned, and every bottle of oil I've purchased, the professionals tend to recommend somewhere in the 3-6 months to 1 year range (or X miles). Those are likely conservative, for liability reasons. In any event, your advice of 2 years is beyond acceptable owners manuals and oil company recommendations, to my knowledge. Therefore I think 2 years is pushing it on time in an engine exposed to elements, as we have agreed that oil does in fact degrade from sitting in an engine at some point.

ETA: No sense arguing about it, certainly many people will have differing views based on the myriad of life events, education, experiences, etc. I never come to forums to argue with people. No point in that misery. But when speaking on terms that might impact someone, I try to speak in clear terms to help others. But we're all only human, trying to assist others with our best suggestions.

 

[FCD]

But you said it does not go bad and does not degrade. 50 years was used to illustrate a point. Intentionally. I'm a literal person. Perhaps your incorrect uses of absolute terms was implied, or just clumsy. I'll give the benefit of doubt it was just flippant terminology.

But now we agree that clearly it does go bad, does get contaminated from sitting, and does degrade. Now that we agree that it goes bad and degrades, the key is to determine at what point. Is it at 40 years? 30 years? 5 years? 1 year? While you are quite likely correct that in 1 or 2 years it probably does not go bad from sitting, at what point does it go bad. "Never" or "Does not degrade" is the wrong answer on a forum that is meant to be more technical in nature. It would be similar to a lawyer speaking in incorrect technical absolutes on a legal forum. It would be ill-information. Further such absolute terms totally contrary to known accepted industry standards and recommendations would undermine that attorney's credibility IMO.

According to every owners manual for every vehicle I've ever owned, and every bottle of oil I've purchased, the professionals tend to recommend somewhere in the 3-6 months to 1 year range (or X miles). Those are likely conservative, for liability reasons. In any event, your advice of 2 years is beyond acceptable owners manuals and oil company recommendations, to my knowledge. Therefore I think 2 years is pushing it on time in an engine exposed to elements, as we have agreed that oil does in fact degrade from sitting in an engine at some point.

ETA: No sense arguing about it, certainly many people will have differing views based on the myriad of life events, education, experiences, etc. I never come to forums to argue with people. No point in that misery. But when speaking on terms that might impact someone, I try to speak in clear terms to help others. But we're all only human, trying to assist others with our best suggestions.

If it was the case that the vehicle in question was short tripped a lot i would not go more than 1 year either, but since it isn't , 2 years would be fine imo, but whatever, let op decide.

 

[Nesterenko]

What certifies you as an oil expert?

I'm not. You're the one giving advice and even warnings to some members. Just check what you've posted in this thread.

 

[ecotourist]

I can tell you that extending my oil change to a year in my Accord did not work out but it sees primarily sort trips. For that type of use I now max out at 5K/6mo.

What happened to the Accord? V6 or I4?

 

[gregk24]

What happened to the Accord? V6 or I4?

It has the I4 (K24). I've owned it for 8 years and have used it on the same commute the entire time, that is 1 mile 4 times a day. It is used primarily for short trips and doesn't often reach full operating temperature. It wasn't until I started pushing 1 year OCI's that the valve train developed varnish. It was always factory new under there until the 1 year OCI. No issues with PCV valve, though I changed it anyway since it is so cheap.

 

[barryh]

For me the question is simple; would I drive 5-6000 miles with little to no short tripping, on one change of high quality oil and still expect that oil to be reasonably in spec with minimal additive depletion.

The answer is yes and the fact that it may take up to two years to do it is almost irrelevant.

 

[kschachn]

But you said it does not go bad and does not degrade. 50 years was used to illustrate a point. Intentionally. I'm a literal person. Perhaps your incorrect uses of absolute terms was implied, or just clumsy. I'll give the benefit of doubt it was just flippant terminology.

But now we agree that clearly it does go bad, does get contaminated from sitting, and does degrade. Now that we agree that it goes bad and degrades, the key is to determine at what point. Is it at 40 years? 30 years? 5 years? 1 year? While you are quite likely correct that in 1 or 2 years it probably does not go bad from sitting, at what point does it go bad. "Never" or "Does not degrade" is the wrong answer on a forum that is meant to be more technical in nature. It would be similar to a lawyer speaking in incorrect technical absolutes on a legal forum. It would be ill-information. Further such absolute terms totally contrary to known accepted industry standards and recommendations would undermine that attorney's credibility IMO.

According to every owners manual for every vehicle I've ever owned, and every bottle of oil I've purchased, the professionals tend to recommend somewhere in the 3-6 months to 1 year range (or X miles). Those are likely conservative, for liability reasons. In any event, your advice of 2 years is beyond acceptable owners manuals and oil company recommendations, to my knowledge. Therefore I think 2 years is pushing it on time in an engine exposed to elements, as we have agreed that oil does in fact degrade from sitting in an engine at some point.

ETA: No sense arguing about it, certainly many people will have differing views based on the myriad of life events, education, experiences, etc. I never come to forums to argue with people. No point in that misery. But when speaking on terms that might impact someone, I try to speak in clear terms to help others. But we're all only human, trying to assist others with our best suggestions.

My, my "leadcounsel", that's quite a rant.

The reason owner's manuals state that is because the automaker does not know how the vehicle is operated during that year. If there is extensive short-tripping then one year may be optimistic. But on the other hand if the year was only longer operation then it is a very different situation.

And unless there are the products of combustion (mixed with water) then there is nothing to degrade the oil within that time frame. It is the mixed sulfur oxides that are the problem here. Gasoline can be a problem as well, but there again the trip length has an impact.

But like you said there is no sense in arguing about it, right? Best to be a human and assist others. However, I do think that your unwarranted extrapolation to 1970 was a bit extreme.

 

[The Critic]

The reason owner's manuals state that is because the automaker does not know how the vehicle is operated during that year. If there is extensive short-tripping then one year may be optimistic. But on the other hand if the year was only longer operation then it is a very different situation.

Valid point(s). The other issue is engine design - oil temps in my truck are >210F after a 5-7 mile drive in town. That is not the case with my Prius. The engine where oil warms up more quickly is more likely to burn off moisture, versus the other.