Heck, if I could just get the FLeetguard folks to release a Nanonet version of anything I could fit on my vehicles, I'd buy a case at $20 each.
why OCI's are variable ?
- Thread starter gasman556
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Fuel delusion and viscosity breakdown for me.
I was able to counter viscosity loss of 5w-30 by filling just past the low mark and adding 20w-50 oil over the oci. Now I'm running 10w-30 so that should help some.
I was able to reduce fuel dilution by not doing any short trips other than my wife driving the car to work, running the car in sport mode when driving on the highway going to the next town over during winter.
I was able to counter viscosity loss of 5w-30 by filling just past the low mark and adding 20w-50 oil over the oci. Now I'm running 10w-30 so that should help some.
I was able to reduce fuel dilution by not doing any short trips other than my wife driving the car to work, running the car in sport mode when driving on the highway going to the next town over during winter.
5. particulate accumulation, something not dissolved.
I can't believe nobody has brought this up yet: the nut behind the wheel!
The BITOG crowd may actually go into anaphylactic shock just thinking about this, but the average person gives absolutely no thought to engine oil, OCI's or car maintenance in general. Its like taking the trash out. They have to do it, but will put it off until the last possible moment. Even mechanically inclined folks might only feel a twinge of guilt.
So the YT mechanic gets told by his customer: " Oh yeah, I change my oil regularly, per the manufacture." When he or she really knows, it gets done when they remember, feel bad for their car, or father goes bananas.
So I can see why mechanics want to push the 5k OCIs. I'm guessing they still have customers who say to themselves:" Hmm, something doesn't sound right. When did I have the oil changed? Is that sticker pre-Covid?"
The BITOG crowd may actually go into anaphylactic shock just thinking about this, but the average person gives absolutely no thought to engine oil, OCI's or car maintenance in general. Its like taking the trash out. They have to do it, but will put it off until the last possible moment. Even mechanically inclined folks might only feel a twinge of guilt.
So the YT mechanic gets told by his customer: " Oh yeah, I change my oil regularly, per the manufacture." When he or she really knows, it gets done when they remember, feel bad for their car, or father goes bananas.
So I can see why mechanics want to push the 5k OCIs. I'm guessing they still have customers who say to themselves:" Hmm, something doesn't sound right. When did I have the oil changed? Is that sticker pre-Covid?"
OVERKILL
$100 Site Donor 2021
Not going to lead to much of a "discussion" if you just refuse to acknowledge facts and nuance. This isn't really something you can "agree to disagree" on, either you acknowledge that the Honda OLM being discussed with those you are discussing it is not simply a mileage counter as you've claimed and they've evidenced, or you willfully refuse to accept that relevant information, in which case there's really no reason to continue conversing.
TBF, I'm trying to keep this thread on point and not derailed into something better suited for a Honda forum.
OVERKILL
$100 Site Donor 2021
But it's germane to the overarching discussion.
Oil doesn't age in miles.
What ages an oil are the various inputs: heat, oxidation, contamination (fuel, soot, acids...etc.) and its ability to resist these inputs is dictated by sump size (dilution) and formulation (additive package, base oil selection).
A vehicle traveling a specific distance says nothing as to the impact of those inputs on the lubricant. It's like buying new shoes every 4 months without taking a look at how they have worn; with absolutely no consideration given to how they were used.
IOLM's (IE, not mileage counters) are programmed to account for operating conditions so that you are changing the lubricant when it's likely to be reasonably contaminated, based on those inputs and not dumping perfectly serviceable product for no reason.
The caveat of course is that IOLM's are programmed based on whatever standard the OEM calls for. That could be Dexos, API SP...etc. So it has no way of being adjusted for oils capable of drains beyond what those minimum standards dictate. This is where UOA's enter the picture.
All of this.
OLMs are looking at several parameters and essentially doing a real-time multiple linear regression on them, finding the best fit curve, then extrapolating from that to some limit.
The issue I have with OLMs is not that they aren't sophisticated or capable. Rather, my issue is that they are tuned with an element of marketing involved. The engineer might want 5k OCIs but the marketing people want to market 10k OCIs. And the engineers begrudinging provide the data that shows, yes 10k OCIs will indeed present little to no risk during the warranty period. So the engineers lose to the marketing people.
I've seen similarly many times. I've been that engineer and lost that conversation. The calculation is simple-- there's no warranty cost savings benefit to the OEM by using shorter OCIs, but there is marketing utility in the longer OCIs. And especially since many cars are now sold with service contracts and free oil changes for some period, dealers want longer OCIs because short OCIs are all cost to them and NO benefit.
So the MBA in me has to concede-- the long OCI calibrations of the OLMs is the correct call from a business case perspective.
But as a consumer and engineer, I will tell you that what's best for for the product durability and my tenure as an owner is NOT what is best for the OEM and its business.
So if you are going to keep the vehicle only as long as its in warranty and stay within the OEM's assumption, you can follow the OLM with confidence. But if you are keeping vehicles a LONG time, the OLM is not sufficient to keep the engine clean and in peak mechanical condition. It was never intended to be.
I recall a hallway conversation when I was working on the X15 for 2010 about extended oil drain intervals. The basic takeaway of that conversation was to the effect of: "Our major fleet customers are keeping the trucks three years and getting two years of warranty. They care about operating cost while they own it. If the engine is nearly used up in 500k miles, they don't care-- they will wholesale the truck after 3 years. Heck, many are leased now and trucking companies don't even own them. So yes we will push things with 35k or 50k OCIs and lower viscosity (5w30) oils tuned for MPG. Because 0.1mpg improvement is about $5000 per year per truck in cost savings to a large fleet."
To this day, I still wrestle with the tension between what my brain knows makes business and financial sense and what to my engineering soul just feels so wrong.
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Patman
Staff member
Totally disagree with that. There is a C5 Corvette in the Corvette museum that has almost 800,000 miles on it and the owner followed the OLM its entire life. Same with the 430,000+ mile C7 Corvette that I know about also. I’m currently at 268,000 km on my Civic following the OLM so it’s way beyond the warranty and running perfectly and I expect it to continue that way.
I followed the OLM in my old C5 Corvette and it had 215,000 km on it when I sold it and that LS1 engine didn’t consume much oil at all (which is rare for an LS1) I have been following the OLM in my 2018 Corvette and it’s only at 106,900 km but I have every confidence that I will see high mileage with this one too.
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Reading BITOG , having my coffee, in a car with over 530,000 KMS that doesn’t use any oil and I followed the OLM ( even went far beyond many, many times ).
And I did 5k oci’s and burn oil…totally engine dependent.
You can say that, but you would be wrong.
I encourage you to look up the Honda OLM.
It's quite sophisticated.
On Item 5 - Oxidation would be a good addition to your list.
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Motor oil deteriorates with TIME, although the rate seems slower while it is inside a sealed container.
RUNNING TIME (hours) is a popular factor for industrial equipment.
CALENDAR TIME is more "extreme". In general aviation, some engines require annual oil changes, even with zero hours. Those are extreme conditions with leaded fuel. Our GM cars have a OCI alert that seems to have 1 year as a factor (GM highlighted some other factors in factor documentation like mileage, driving habits, etc but I can't remember them).
RUNNING TIME (hours) is a popular factor for industrial equipment.
CALENDAR TIME is more "extreme". In general aviation, some engines require annual oil changes, even with zero hours. Those are extreme conditions with leaded fuel. Our GM cars have a OCI alert that seems to have 1 year as a factor (GM highlighted some other factors in factor documentation like mileage, driving habits, etc but I can't remember them).
The PDF I have is protected, but I can snapshot a few bits from it to give an idea of what it looks at when it calculates remaining oil life. It's a penalty based system that monitors a number of inputs.
This also answers some of your original question as to the variability of oil life.
This also answers some of your original question as to the variability of oil life.
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But confirm your Subaru didn't have an OLM?
You said you changed the oil every 5000 miles, but what did Subaru recommend out of curiosity?
No OLM. Subaru recommends 6k miles. Reduced from 7500 miles a while back.
Maybe cite a more relevant example next time. A vehicle with Mobil1 as factory fill suggests that operating cost isn't the #1 factor for that vehicle.
Your example doesn't rebut my point. It's a red herring.
Find a Toyota or Kia that did the same thing on factory 5w20 or jiffy lube commodity oil and you'll have a good rebuttal point.
As it should be, because fuel dilution degrades about as badly as high temp oxidation.
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