Updated spec oils in older spec engines

ZiTS

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I never said one thing about timing chain wear.
I never said one thing about wanting to still use SN rated oils.
I never said one thing about price being related to oil specs.

My original post is simply asking what, if any, benefit there is in using more expensive oils in older cars, when a less expensive modern oil still exceeds what that engine was designed for. My posts have never strayed from that. Everyone else was inserting comments that had nothing to do with the original question.
 
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I never said one thing about timing chain wear.
I never said one thing about wanting to still use SN rated oils.
I never said one thing about price being related to oil specs.

My original post is simply asking what, if any, benefit there is in using more expensive oils in older cars, when a less expensive modern oil still exceeds what that engine was designed for. My posts have never strayed from that. Everyone else was inserting comments that had nothing to do with the original question.
I think what you are not seeing is basic engine design hasn't changed much in the last 50 or 60 years. The oils we used years ago were garbage but it was the best and only thing we had. Oil requirements for newer vehicles hasn't really changed much but what modern oils can do has. Keeping engines clean, reducing LSPI and chain wear to a minimum, increasing MPG and decreasing wear. Our old engines will benefit greatly by using modern oil be it conventional or synthetic the same as a modern engine.
 
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My feeling is that in some cases like your Ecoboost or really most DI, turbo engines and chain eaters the newer specs were designed because there seemed to be a problem that was not addressed in the older spec and the less expensive oils were failing to provide enough protection. After all with the exception of people on this forum who really looked to see if the manufacturer spec was listed on the back of the bottle. So in reality unless you are extending your drain you are not gaining anything with the really high priced stuff. And in the case of the real old engine you may actually be getting hurt. Even though they are backward compatible if you have a car before catalytic convertors you might really want more ZDDP than the current spec allows.
 
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I never said one thing about timing chain wear.
I never said one thing about wanting to still use SN rated oils.
I never said one thing about price being related to oil specs.

My original post is simply asking what, if any, benefit there is in using more expensive oils in older cars, when a less expensive modern oil still exceeds what that engine was designed for. My posts have never strayed from that. Everyone else was inserting comments that had nothing to do with the original question.
If the less expensive modern oil exceeds the original equipment oil specs, then there is little difference in the life of the engine using more expensive oil using the original recommended OCI and driven as a normal average vehicle, IMO.
 
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Oil of older specifications disappear over several years after the newer ones come out. You probably cannot find the older ones in just a few years after the newer ones are on the shelves. So, by default you'll have little to no choice but to use the up to date oils. I think other poster have made it clear that every API license is backward compatible. I think they have covered this quite well.
 
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Just to clarify, I don’t want to limit this strictly to my engine and SN/SN+/SP oils. Those are simply my particular situation. I would like to discuss this for any/all engine and continually advancing oil specs.

I definitely don’t want to compare SP to SN, either. I’m wanting to know why a person would spend more money on the most advanced oils out there for an engine that was never designed for it.

Engines aren't exactly "designed for an oil". It's more that the engine design dictates the minimum acceptable requirements for the oil. A superior oil with more stringent requirements may offer advantages. For instance, as we have alluded to - the fact that SP rated oils now have requirements specifically oriented around extending timing chain life. Any engine using a timing chain will likely benefit from an SP oil, although it is possible that the older SN rated oil you were previously using might meet the newer SP specification. You simply have no way of knowing unless the manufacturer is willing to make that statement to you (which is very unlikely).

However, one can't make blanket statements of the sort you seem to be seeking. Will any particular engine benefit from a particular upgrade in oil specs? That depends on the engine and the oil. About the best you can say is that in general more modern oils made to more stringent specs will be superior to older oils made to less stringent specs. Whether that is material in your specific case is for you to decide. But it is certainly not that case that an engine must be "designed for" a newer spec oil in order to take advantage of it's benefits. This isn't like putting a faster ram in an older computer.
 
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How would you determine that with real data, rather than anecdotal claims?


A couple of recent examples; LSPI which after research it was determined that high calcium in oil was part of the problem. Calcium is used as a detergent so the oil manufacturers developed a lower calcium additive base. Thus, SN+. Also, a increase in timing chain and guide wear prompted oil manufacturers to develop oils that fought this better. This is SP.



As engines evolve with different designs and ideas the oils will follow.
 
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Forget about my engine for a minute. Pick whatever older engine you want. Let’s say it’s a Chevy small block from 20 years ago. Why not just use currently available conventional instead of spending more for currently available fully synthetic “extended performance” oil? They both should exceed any oil that engine was ever intended to have put in it, right?
People that look at all the specs of motor oils have their reasons for buying one over the other. If it meets more of the specs that they think are important, then they will spend a little more of their money for the oil that makes them feel better. Some people don't care about that, or don't care as much about their vehicle for whatever reasons, so they'll just buy the cheapest oil that works with the attitude that "oil is oil". OCI and vehicle use condions are also factors involved with making a wise oil choice decision.
 
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A couple of recent examples; LSPI which after research it was determined that high calcium in oil was part of the problem. Calcium is used as a detergent so the oil manufacturers developed a lower calcium additive base. Thus, SN+. Also, a increase in timing chain and guide wear prompted oil manufacturers to develop oils that fought this better. This is SP.



As engines evolve with different designs and ideas the oils will follow.
Right, but I was responding to "But what if the factory spec'ed lubricant and service intervals were inadequate?" So, since there are no perfect oils and they continue to improve, one could say that "all factory spec'ed oils and service intervals are inadequate", and that is proved by the continuing improvement of oils. Factory spec'ed oils are the best available at the time.
 
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Right, but I was responding to "But what if the factory spec'ed lubricant and service intervals were inadequate?" So, since there are no perfect oils and they continue to improve, one could say that "all factory spec'ed oils and service intervals are inadequate", and that is proved by the continuing improvement of oils. Factory spec'ed oils are the best available at the time.


To clarify, what I have noticed over the years is that the auto manufacturers develop and build engines that test the current specs at that particular time. We saw it in the 70’s and 80’s as smog prevention equipment made oils dirtier. Direction injection and variable valve timing and low tension piston rings are other examples. These developments were done to make engines more efficient in power and fuel economy and they worked. Then issues arose like ring coking and the oil companies had to react.
 
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Since API SP is a min requirement standard, many premium oils that used to be SN+ only had to change label to SP when new standard was released. They often exceed min standards.
 
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Although I cannot verify this to be true, I would think it is quite accurate.
I know when SN+ just came out, mobil1 was proudly saying that their SN oils been meeting SN+ years before the standard. But in general its difficult to say if they update label only or actually change forumation.
 
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Is this a theoretical question? It would be like asking where can one find new 8track tapes. The world has moved on, largely.

SJ was a 1997 rating. SL was a 2001 rating. I recently did an oil change on a truck of that era. I used up several really old quarts of SL and SJ oil, that I probably bought from a garage sale 10+ years ago. It served its purpose for a short (a month, few hundred miles) OCI. Other than some garage sale, where would one even economically find, say, SJ or SL oils?

I'm regularly buying, retail sale and clearances, SN, SN+, and SP fully synthentics or blends for $1 to $2 per qt. Literally, $6 per 5 qt and $8 per 5 qt deals. How much cheaper could a person want oil to get? Inflation adjusted, I was paying more for conventional oils in the 1990s. Here's a portion of my oil collection, average price about $1 per qt. All premium new oils.
Resized_20210801_205858.jpeg


From a practical standpoint, if some had a car from 1999 that needed the best oil of the era, SL category, it would probably be fine. The issue is a reliable source for that oil, and I doubt one exists because they become both obsolete and backward compatible and also probably vastly improved with additive packages. Some make oils specifically marketed "for older cars and trucks." But I doubt they revert to SL categories.

The newer oils are superior in every regard and with wear packs and detergents not available 25 years ago. And often at a price competitive or better than inflation adjusted 1999 dollars.
 
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