cant speak for all, im my 18 f150 it generally puts me around a 7500 oci and that's what the empirical formulas calculate as well. so they are probably similar in how the oci is calculated.
OCI: Engine Hours vs. Mileage
- Thread starter The Critic
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I view this as an interesting discussion, but I've come to learn that auto manufacturers have done a pretty good job at their OCI recommendations, with a few notable exceptions (GM) in the early days of IOLM. Most modern autos have IOLMs that take into account way more wear factors than we're talking about in this thread. While at first skeptical of IOLMs, I've come to rely on them, at least in in my Ram truck. My wife's Hyundai has an oil change "reminder" based solely on mileage--I'm OK with that also, as I get to set the mileage that it goes off, which is set with our driving habits in mind, as well as calendar days recommended by H/K. My Ram usually times out (one year) before the oil wears out, otherwise I'd run the IOLM down to the 10% range.
Good discussion, but my advice is, use the IOLM if you have one. . .if not, follow the engine manufacturer's recommendations and try not to over think it. . . but this is BITOG, I know. lol
Good discussion, but my advice is, use the IOLM if you have one. . .if not, follow the engine manufacturer's recommendations and try not to over think it. . . but this is BITOG, I know. lol
It would be kind of neat if you could track the total number of engine revolutions.
Rpm x minutes if the engine runs at a constant rpm, otherwise you would have to make the computer count every revolution individually
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I guess the best practice would be averages/norms.
If I drive 30 minutes one way to work 5 days per week, and drive to some place on the weekends for also, about 30 minutes one way, and I know the miles (lets say 25 miles to work one way, and same for what ever weekend trips I do) then you can calculate that I drive (as an example) 300 miles per week, for 6 hours of total driving. If I change my oil at 5000 miles, that is 16.66 weeks, or 100 hours of driving.
If you have an oil analysis history of your OCI's and the wear and oil is fine at those OCI's then what does it matter, but if there was an OCI that was "adverse" or "out of the norm", then you can do the math for how much more hours your engine ran for how much extra wear happened (if it happened at all).
But total RPM is something I have thought of as well.
If I drive 30 minutes one way to work 5 days per week, and drive to some place on the weekends for also, about 30 minutes one way, and I know the miles (lets say 25 miles to work one way, and same for what ever weekend trips I do) then you can calculate that I drive (as an example) 300 miles per week, for 6 hours of total driving. If I change my oil at 5000 miles, that is 16.66 weeks, or 100 hours of driving.
If you have an oil analysis history of your OCI's and the wear and oil is fine at those OCI's then what does it matter, but if there was an OCI that was "adverse" or "out of the norm", then you can do the math for how much more hours your engine ran for how much extra wear happened (if it happened at all).
But total RPM is something I have thought of as well.
I have an IOLM and an hour meter. I start planning my change when the IOLM hits about 30%, sometimes it gets down to around 25% if I'm not paying attention. One thing I miss about the older (2012 in particular) F150 was that I could start the IOLM at 90% and it dinged a reminder at 20%.
We overthink a lot. We solve problems on here that don't exist.
We certainly try to reinvent the wheel, or at least give it a design upgrade..... We forget that for at least 3 decades automakers have been building engines that easily go 300k on 7500 mile OCI's. It ain't 1983 anymore. Do people still blow up motors. Yup. Does it happen to people who take care of their cars? Yup. Machines occasionally break because crap happens. I've broken sockets on fasteners that weren't on that tight. I've broken can openers on tin cans. I've broken pocketknives simply by using it as a pocketknife - but Ford GMC FIAT BWM Subaru etc.... all build engines that will run dang near forever with minimal effort.
Does Ford have sloppy cam phaser problems? Yes.
Does FIAT have problems? Yes.
GMC - you betcha.
So on and so forth.... Few of them are a product of oil neglect - ie not changing it around 7500. You go 20k on Bobo's Slickery Oil and you might have a problem that IS oil related.
Just my .02
We overthink a lot. We solve problems on here that don't exist.
We certainly try to reinvent the wheel, or at least give it a design upgrade..... We forget that for at least 3 decades automakers have been building engines that easily go 300k on 7500 mile OCI's. It ain't 1983 anymore. Do people still blow up motors. Yup. Does it happen to people who take care of their cars? Yup. Machines occasionally break because crap happens. I've broken sockets on fasteners that weren't on that tight. I've broken can openers on tin cans. I've broken pocketknives simply by using it as a pocketknife - but Ford GMC FIAT BWM Subaru etc.... all build engines that will run dang near forever with minimal effort.
Does Ford have sloppy cam phaser problems? Yes.
Does FIAT have problems? Yes.
GMC - you betcha.
So on and so forth.... Few of them are a product of oil neglect - ie not changing it around 7500. You go 20k on Bobo's Slickery Oil and you might have a problem that IS oil related.
Just my .02
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My personal favorite is October and April!
