I just had a mechanic tell me that the engine on my old Saturn (2001, 200K miles) is shot because of years of low-quality oil used in the engine. He said there is oil in all the cylinders and the rings are bad. He attributes the damage to years of using “low quality” oil. I have never heard this before. Losing an engine to not changing the oil or letting the oil get low I certainly understand. But has anyone ever heard of engines being damaged/destroyed by years of low quality oil?
This mechanic named names, but rather that get into debates on whether this or that oil is good or bad, my question is limited to are there low quality “name brand” oils? In the sense that prolonged usage will actually damage the engine?
ISTR reading an article that reported measurements of the critical anti-wear additives (like [urlhttps://en.wikipedia.org/wiki/Zinc_dithiophosphate]ZDDP in various oils. Some had more than others. The various API standards over time have indirectly limited ZDDP content (by limiting phosphorus content); some oils came closer to this limit, while others had relatively little ZDDP.
I don’t know how much ZDDP you need before you’ve got a “good” oil that will enable your engine to last notably longer. At 200K miles, I wouldn’t necessarily blame a lifetime of cheap motor oil; lots of cold-starts and short trips (to name a couple of other culprits) could easily make the engine wear out faster, too.
For example, for gasoline engines, API Categories SJ, SL, SM, SN are current. Category SN (the most recent) was introduced in 2010 for “2011 and older vehicles.”
I recall a Consumers’ Report article from something like 20 years ago regarding a study on NY taxi cabs. As long as the oil had the API rating, and was changed on schedule, there was no difference between oils.
For that reason I’ve been buying whatever is on sale at the time and have had no issues.
I have used cheap oil all of my life, and I routinely drive cars until they have at least 200,000 miles on them. I’ve never had oil cause engines to wear out prematurely. I’m rather skeptical that it could.
A lot of folks seem to think that engine oil is critical. In most cases I don’t think it is. Using cheap oil and going a longer time than recommended between oil changes won’t usually harm your engine, at least not in my experience. I had an old Nissan truck that I wanted to get rid of. The engine ran fine, but the body was rusting off of it (my friend nicknamed it the “Bondo Bandit”). So after it hit 200,000 miles, I decided to have a bit of fun with it and I stopped doing any maintenance on it at all, which includes oil changes. I wanted to see how far it would go before something major broke, at which point I would scrap it and buy a new truck. A few years later, at 260,000 miles, the fuel pump died on it. The fuel pump on that model truck is in the fuel tank, so it just died from old age and wasn’t at all related to my lack of maintenance on the truck. But the engine ran perfectly and it didn’t lose a drop of oil. I could have fixed the fuel pump but by that point I was sick of the truck and just wanted a new one so I junked it. It did rather prove the point that you don’t necessarily need to change the oil every 3,000 miles. Some people think your engine will explode if you wait until 5,000 miles. That engine went 60,000 miles with no sign of anything at all bad happening. I suspect it would have gone a lot longer. And that was el-cheapo walmart oil.
On the other hand, an old Toyota Camry we had would start to sludge up if you went too long between oil changes. Some engines are prone to sludging. Some aren’t. I’m just an idiot backyard mechanic, but from what I’ve read about it the pros don’t seem to have a good handle on why some engines sludge up so easily.
In my experience, how you drive the engine makes the biggest impact on engine life. Do a lot of hard accelerations and the rings will be shot after 100,000 miles. Accelerate gently and keep the RPMs low it and the engine will be perfectly fine well past 200,000 miles. That’s what makes the most difference, not which engine oil you use.
Oil burning and varnishing issues occur in Saturns of that era. There are no drain back holes in the pistons. This allows oil in the oil control rings to overheat, and eventually form a hard varnish… which freezes the oil control rings in place. This isn’t good for lubrication, clearances, etc. In these cases, a good synthetic oil (high flash point and better detergency) would have been called for.
In cases where the engine has a particular flaw, such as those that sludge, form varnishes, etc, then a high quality oil above and beyond the minimum recommendation has value, and that is usually a synthetic.
Hey, some wise Porsche owners even ignore Porsche, who’s in bed with Mobile, and opt for some Euro synthetic oils because they have higher zinc contents, which help mitigate some design flaws in those engines, so it ain’t out of the question that a Saturn engine would have a flaw that could be mitigated by top notch oil (synthetic).
Thanks for all the replies!
That is my experience as well. The car hadn’t been maintained as well as I normally would and after 200K I think I got my money’s worth. I bought it used.
As for the new mechanic-yeah he seems like a real nice guy and talks like he knows cars but there are a are red flags… It is a long story but I didn’t get to pick him and actually haven’t met him yet. The car died on the road and he was the one person who offered to help at an awkward time.
To his credit, when he couldn’t fix the car he refused any payment for his time. He had made a couple of tentative diagnoses and encouraged me to let him pursue the repair effort. I let him proceed even though several of his ideas came and went. I will junk the car and move on. Perhaps I will work with him in the future and perhaps not.
Regardless of the oil used, Saturns of that era were oil burners. The engines had repeated problems with rings and 200K might be all that could be reasonably expected. I sold mine at 150K and it was burning oil at a steady (but not ridiculous) rate, maybe a quart every 2000 miles.
I doubt your mechanic is trained to make analytical judgements like this. A professional lubrication engineer who has analyzed thousands of oil samples over decades can.
There can be a significant difference between engine models and between oils. In some cases you can use inexpensive oil which nominally meets the factory spec and change interval, and in other cases it’s better to use something else and/or shorter intervals. It can even vary on a specific engine over the life of the car.
The problem is you have no way of knowing except for having professional oil analysis and detailed individual interpretation by an experienced lubrication engineer. Unfortunately that can be somewhat expensive (about $150).
Several years ago, they REMOVED the “ZDDP” from motor oils and DID NOT TELL ANYONE (you and I)!!!
ZDDP can still be found in diesel engine motor oil or you can use fully synthetic motor oil.
I’m told older car engines need the ZDDP in the oil, but newer cars do not.
Note: The reason I know about this is I had a rebuilt engine installed in my truck and I received a warranty notice informing me of this problem. The mechanic said a few years back they started getting rebuilt engines returned - ruined in a short period of time because of this.
Anyway I use diesel engine motor oil in all my 4 stroke small engines and my truck. Use fully synthetic oil in a '90 car. And use off the shelf new oil for a new 2012 car (does not need ZDDP).
Note the diesel oil will smoke in a car with high mileage, so better to use synthetic.
ZDDP has been gradually reduced because it can contribute to catalyst poisoning. Modern diesels have three catalysts in the exhaust and there’s no guarantee that API CJ-4 oil has any more in it than SM/SN.
2/ people who are convinced by engine oil salespeople to pay for expensive engine oil and who want to convince everyone else, lest they feel like the saps they are.