The Fallacy (fallacies?) behind "It's cheap insurance"

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Diesel Central, Indiana
A recent post contained a phrase to the effect of "oil is cheaper than an engine." Well, yes it is. But there's some really sloppy thinking represented in that conventional wisdom that makes it not actually wisdom at all. Something about that phrase always bothered me, I think I've figured out why it does bother me.

I think the main reason it bothers me is because it's just to justify almost any practice around. Run a premium oil and drain it well before it's done? That's ok, it's "cheap insurance." Run the cheapest stuff and dump it every 2k? That's ok, it's "cheap insurance." Buy a premium oil and stretch it to the limit with UOA backing? That's ok, it's "cheap insurance" to get the UOA done. How absurd must an oil change practice be before it is no longer "cheap insurance."? Dumping HPL every week? Well, it would take something nearly that extreme for a long time for you to spend more on oil than on a replacement engine.

So as far as its utility in discriminating one practice from another as being most economical, the concept of "cheap insurance" is garbage.

Why is this the case-- that it justifies anything we wish? I think it's because it represents fundamentally the wrong question. It's not a matter of whether to change your oil at all. So once you assume that some maintenance must be done, the question is one of marginal cost and marginal benefit.

In other words, the reason the question is perpetual is because nobody can agree on the *incremental* value of the next higher or lower tier of oil or drain interval relative to the incremental cost. It's simply too subjective because nobody agrees on the value of the hassle of oil changes. For some, they enjoy it and it's hardly a hassle at all (BITOGer). For others, it's tolerable. For many, it's just about being as cheap as possible and barely surviving the period of ownership.

Most us around here are indulging the "pristine corpse" tendency in that our vehicles will be hauled off the the crusher or sold or traded in with pristine engines that are over-maintained. We used a better oil that needed and changed it more often that needed because it made us feel better.

Why? Because it's "cheap insurance." Well, still cheaper insurance could have been bought, but we elected not to. Why? Because we are indulging an emotional need to feel smarter or wiser than others by maintaining our engines to pristine cleanliness. By indulging this, the only thing we are "insuring" is our collective egos and sense of well-being.

So let's at least be honest enough to admit it. The truth of the matter is revealed by the phrase " religiously maintained." It's because it satisfies a belief system, provides a sense of peace. It helps us feel superior to the unwashed masses. "Religiously-maintained" indeed! With all the aspects of faith and judgment and emotional fulfillment that comes along with such!

Thus the perpetual thick vs thin or whatever discussions. If it was purely up to reason or empirical results, there's no discussion to be had. The ambiguity-- the tension-- is the entire point.

To the extent that changing oil is insurance at all, it's not relevant to why one would choose one policy or company over another.

So I'd ask we stop using this garbage logic of "its cheap insurance" because that's just terrible thinking. Or if not, just know I'm secretly judging you for using it LOL.
 
It helps us feel superior to the unwashed masses.
I would object to this, I rather do not care what others are doing. They could all be jumping off bridges for all I care--I will not be following them. I do things for my own good/entertainment/satisfaction. Measuring myself against others does not come into play.

Unless if it's measuring my retirement portfolio. Then I smile in glee, and absolutely delight in feeling better than the masses.

[Not really, just poking fun about the last bit--my account is nothing special.]

I do believe that there has been a pattern shown of late, where the OEM recommends a too-long interval--as proven by problems for those who follow it, and by those who short-changed and do not have said problems. Not true for all engines of course--OCI's can't fix everything--but between chain wear and ring clogging, a few engines have shown this to be prudent, when there is no history to prove otherwise.
 
I do believe that there has been a pattern shown of late, where the OEM recommends a too-long interval--as proven by problems for those who follow it, and by those who short-changed and do not have said problems. Not true for all engines of course--OCI's can't fix everything--but between chain wear and ring clogging, a few engines have shown this to be prudent, when there is no history to prove otherwise.
Can you give some examples of this? I think people extrapolate a few outliers as the rationale for doing what they do whether or not it's applicable to their engine.
 
I used to think that as well. That it's a waste to change too frequently or use boutique but threads like these have made it really seem like it is cheap insurance if one doesn't know for sure if the engine is known durable. But even if it wasn't people are still free to do what they want. Besides it will get recycled and used for something else so who am I to care. In threads like these it's not so much oil choice or viscosity but frequent intervals that help weak fragile engines last. Those that had engines susceptible to oil consumption. stretched chains, or other wear didn't get punished from it with religious changes.

 
The problem with engines, or tires for that matter, is that they get changed in design at just about the interval where they wear out. So if one has a positive experience and wants to buy another "just like the last one", they cannot. So they trust the manufacturer to make the sequel as good as the original.

But then we see an engineer change something small, that turns out to be big, causing unpredicted shortening of an engine's life. Sludging. Whatever's going on with GM's 6.2. So the "smart" money's on either an engine family that's gone unchanged for a decade or for OCIs or viscosities that were used ten years ago.

You also see posts here where someone legitimately wants to change their oil early and is looking for affirmation. They argue with those who say no and agree with the yes people.
 
I do believe that there has been a pattern shown of late, where the OEM recommends a too-long interval--as proven by problems for those who follow it, and by those who short-changed and do not have said problems.
Point that out for anything else and people will tell you "correlation doesn't equal causation" though 🤣
 
Think if you will, about all the vehicles that are on the road in the united states right now, Today. All the different brands of vehicles, all the types of vehicles, all the sizes of vehicle engines, and all the brands of oil people are using. Cheap oil, expensive oils, middle of the road oils. And oils that are fresh in their engines, oils that are way overdue to be changed, and oils that read low on their dip sticks. And those vehicles keep on going day after day, month after month. That is something that can't be ignored. A vehicle's engine is the toughest part of any vehicle. In most cases, it will still be around and working after the trans gives up, the AC quits, the windows stop going up or down, the brakes wear out , or the body and frame and suspension parts rust to pieces. So it would be hard to say the saying "any oil is good oil", or " Oil is cheaper than an engine", isn't one of the truest statements in the automotive world.,,
 
Point that out for anything else and people will tell you "correlation doesn't equal causation" though 🤣
I think the OCI or oil quality is really the only variables for many of each vehicle models now. As for example, almost every Corolla is getting the same gas, driven by the same types of people, they are all automatics now, so no one can lug it, not too many have remote start, and almost nobody is driving them very hard, almost no one is towing, etc. They all run with OEM thermostats for 10+ years, and the cooling system is sufficient regardless if anyone changes the coolant or not.
I guess short tripping vs long tripping is a factor, but that is easy to determine and maybe sort the results based on that?

I think using good oil is "cheap insurance" for the DIY'r on any vehicle, as it doesn't cost that much more. And if your situation warrants it, shortening the manufacturers OCI could help prevent a known problem from occurring, especially if you are running the oil cold or hot for most of your OCI(short tripping or running the engine very hard).
IMO For people long tripping on highways mostly and not towing, that's ideal conditions, so shortening the manufacturers OCI is almost certainly a waste of time and money.
 
Can you give some examples of this? I think people extrapolate a few outliers as the rationale for doing what they do whether or not it's applicable to their engine.
I'm a bit of Toyota fanboi so the 1.8L's used in Corollas come to mind, along with the 3.0 FWD's and the later 2AZ-FE's. All were prone to clogging oil control rings and becoming oil burners--but for those who followed a short change interval, they seemed to avoid. [There has been some speculation that the problem lay with owners going past OEM recommendation and/or using conventional, but it was enough to have some level of recalls.]

I believe the Saturn 1.9L falls into the same category (although I have heard those suffered from weak rings too). Recent threads about Honda's K24 is starting to indicate that they like to burn oil at high miles.

There has been some debates about timing chains not doing well with 0W20--but clearly some OEM's are fine with 0W20. Very manufacturer dependent. Cam phasor problems too?

Not sure on the prior DI engines that were known to build crud on valves (again, not all early DI motors did this, but there were plenty that did), I want to say, they wanted good oil but still had a need to clean valves.

Honda's VCM engines seem to suffer, if VCM is not disabled.

Now the bad cams found in GM, Dodge and whoever else, that does not seem to be OCI related. Materials problem? bad cam followers/lifters.
 
I think the main reason it bothers me
Why be so self absorbed that people doing something different is bothersome. How can it possibly hurt you?
So I'd ask we stop using this garbage logic of "its cheap insurance" because that's just terrible thinking.
Please quantify? Do you have proof its terrible thinking.
 
Draining a good quality oil before 5,000 miles is a "money flush". There is no doubt about it. I just bought a Volvo XC60 for my wife-Volvo recommends a 10,000 mile OCI. While I don't know if I will go that far-I will exceed 5,000 miles. I might settle for 7,500 to 8,000.

There are some wild claims made on here based on "seat of the pants" or my motor runs smoother testing.
 
imho when people are of means, it's fun, it's comical, and it's downright amusing. People here have stated they throw away tires at age 6, regardless of tread. Can you imagine doing that anywhere else? I ain't too proud, I've got tires from 2007 still being used, and they are absolutely fine. My Pilot Super Sports to me are supercar tires. They came standard on 599GTBs. They are from 2014. I'm not throwing them away, I'm driving on them daily. And I try to change the oil at the right time. Sometimes I think people are boasting when the propose changing it after 100 miles. You don't come across as superior when that is done. I already know people have money on this forum, that's not a way to impress.

There was a time, admittedly, when doing brakes, I have thrown away pads with 40% left, "Because I"m in there already." I grew up. I don't do that anymore. I wait until the rotors are scored by the rivets of the pads. All kidding aside, it it did happen a bout a year ago, the squealer hit the rotor. No damage, but that's only one time I ever took it that far.
 
Can you give some examples of this? I think people extrapolate a few outliers as the rationale for doing what they do whether or not it's applicable to their engine.
How about this as an example. My toyota says 10K OCI. Then it says if you fall into these use cases its now 5K intervals. Are we to assume these use cases are the only ones? What other sets of conditions might emulate this. For example, it says "heavy vehicle loading" but gives no specifics. What is heavy loading? 1/2 rated load. 80%?

I think one can infer that there are lots of use cases where Toyota themselves think 5K is better, and then the owner is left to try to figure out where the line is. So might be just as easy to go with 5K.

Like this whole thread - its nebulous.

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There are also fallacies from years ago like: a good dino oil can go 5K miles, and a good synthetic oil can go 10K miles. Completely skipping the vehicle or how it was being used.
I just assume severe service interval. I prefer my oil to be the grade I put in when I take it out. If I'm giving up 1-2k on an oci for that, I don't lose any sleep. Not going to run the jeep out to 7.5k+ oci.
 
How about this as an example. My toyota says 10K OCI. Then it says if you fall into these use cases its now 5K intervals. Are we to assume these use cases are the only ones? What other sets of conditions might emulate this. For example, it says "heavy vehicle loading" but gives no specifics. What is heavy loading? 1/2 rated load. 80%?

I think one can infer that there are lots of use cases where Toyota themselves think 5K is better, and then the owner is left to try to figure out where the line is. So might be just as easy to go with 5K.

Like this whole thread - its nebulous.

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I wish I could say for sure, but I thought I had seen in the 2011 Buick Enclave manual, trans fluid should either be replaced at 50k under extreme use, or if not, not ever. That doesn't seem to be logical. We're living less and less in a world of science, and more and more in a world of folks equipped to go to battle with ChatGPT. We're going to lose, I get it, but we can still exhibit common sense....a Lexus owner's manual is check this, check that, every 5k miles, to the tune of hundreds of dollars. What modern car truly needs it? Their checking can have a LS430 go 10 years and have no coolant in the reservoir or radiator to be seen because it was never actually checked. Dealer serviced all that time yet that's the end result. Or only 7/8 plugs replaced, because one is harder to get to.
 
I wish I could say for sure, but I thought I had seen in the 2011 Buick Enclave manual, trans fluid should either be replaced at 50k under extreme use, or if not, not ever.
The piece your missing is whatever Buick figured the design life of the car was. When they say "not ever" it simply means the fluid will last what they deem to be the useful life of the vehicle. For them 100K might have been the MTBF, so in there engineering world this makes sense.

Most of the time there definition of that number and my definition differ.
 
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