Patman
Staff member
I’m not blaming it on not doing an early change. Just wondering why you are so hostile about it? 
Do any manufacturers still use break in oil?
- Thread starter Patman
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Not that I’ve heard of. Apparently special break-in oil isn’t necessary with modern materials like moly coated piston rings and plateau cylinder honing. The cylinders are mostly broken in within the first few minutes of engine operation.
As an aside air cooled airplane engines still call for non-detergent non-dispersant SAE40-60 plain mineral oil during new engine or new cylinder break-in. However, many mechanics claim there is no harm in using ashless dispersant (regular airplane oil) for break in. I think the main difference is the type of cylinder honing used compared to car engines. Especially on an overhauled cylinder, there are sharp peaks in the honing that are better ground down with a mineral oil without causing glazing. I think the airplane engine factories are using processes similar to cars now and those engines too are broken in fairly quickly (a few hours of run time), but they still stipulate the mineral oil for the first 50 hours or so. When I received my new engine it was already broken in at 4 hours since temps were stable and there was no oil consumption.
Interestingly the only oil that seems to be universally forbidden for airplane break in is any PAO synthetic or blend, of which there is really only one brand/type for airplanes.
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My unknowledgeable opinion: if the debris is minimal enough for a 500 mile oil change having any benefit, wouldn't the filter catch it? If it's more than minimal so the filter can't help much, wouldn't it clog the oil pump, pickup screen, oil galleys, or something else in, say, the first few minutes or miles of driving?
I mean, do what makes you sleep at night, but I feel it hard to believe the engine implosions being recalled would be cured with a change at 500. Or that's what the recall would require because that's a lot cheaper than replacing or fixing an engine. And if there's one thing I know about corporate America, if changing the oil early fixed the issue, that's all they'd recommend.
brake in oil for autos went the way of the caveman..............lol
What stresses are there in pistons that get relrved by heating and cooling cycles? What other parts have stresses that are relieved in such a manner?
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Heating and cooling pistons during break-in, often through controlled engine operation, helps seat the piston rings properly against the cylinder walls, establishing an ideal wear profile and minimizing friction. This process allows the rings to conform to the cylinder walls, ensuring consistent power and compression across all cylinders. [1, 2]
Here's a more detailed breakdown:
- Ring Seating: The initial contact between the piston rings and cylinder walls can be rough. Heating and cooling cycles, especially during the break-in period, encourage the rings to rub against the cylinder walls, wearing down high spots and creating a better seal. [2, 2, 3]
- Minimizing Friction: Properly seated rings reduce friction between the piston and cylinder walls, which translates to less energy wasted and potentially increased power output. [2, 2, 4, 4]
- Internal Stress Relief: Forged piston materials can have internal stresses. Heat cycling helps relieve these stresses, leading to more consistent performance and longevity. [5, 5, 6, 7]
- Improved Combustion: A good ring seal ensures proper compression, which is crucial for efficient combustion and power delivery. [2, 2, 8, 9, 10]
- Heat Transfer: The cooling down period allows heat to transfer from the partially seated piston rings to the cylinder walls, aiding in the seating process and preventing excessive wear. [1, 1]
[1] https://dsportmag.com/the-tech/education/quick-tech-performance-engine-break-in-the-right-way/
[2] https://www.planeandpilotmag.com/article/engine-break-in-its-easier-than-you-think/
[3] https://generatorsupercenter.com/tips-for-breaking-in-your-generator/
[4] https://www.faa.gov/sites/faa.gov/files/08_amtp_ch6.pdf
[5] https://www.adriansmodelaeroengines.com/catalog/main.php?cat_id=99
[6] https://www.jepistons.com/je-auto-blog/bead-blasting-billet-pistons-for-extra-strength/
[7] https://www.teaminc.com/resource/induction-heating-benefits-limitations-and-our-teams-solutions/
[8] https://www.ppuk.com/blog/how-piston-rings-impact-on-fuel-efficiency/
[9] https://www.haldimandsyntheticoil.ca/amsoil-science/engine/how-piston-rings-work/
[10] https://kolbenringindia.com/what-are-the-main-functions-of-piston-rings-in-engine-performance/
Assume what you want. Not hostile at all... You seem to have forgotten that you are the one that asked the original question, then get defensive when others pick one side of the debate.
OVERKILL
$100 Site Donor 2021
Objectively, there's plenty of proof (numerous SAE studies) that abrasives in circulation cause more wear. @ZeeOSix has previously posted studies on filtration that show the same thing: a reduction of particles in circulation reduces overall wear in the equipment. Timken has two pages dedicated to bearing and roller wear due to fine materials in their bearing failure analysis reference guide.You're confusing "policy" with "opinion".
Again, so what ? Prove the long-term implications.
And you automatically blame it on NOT doing early oil changes ?
I don't care if you do it or don't do it. My argument is there's no proof it makes a difference. Almost no automaker recommends it either, but I guess we're to magically believe that these engines will squeak by long enough to make it out of warranty, right, then fail ?
So, taking that at face value, removing those break-in particles, which are abrasive, from circulation, will reduce the wear rate. Now, whether that's significant to the useful lifespan of the equipment is certainly up for debate, like so many other things we discuss on here.
A quote from one paper:
The generation and circulation of a wear debris, particularly in systems where the clearances are small relative to the wear particle size, may be more of a problem than the actual amount of wear. ... which itself has an affect on both the wear rate and the transition loads.
And another quote:
It is more common now for bearings to fail by initiation at sites of surface damage caused by the entrainment of lubricant-borne debris particles [113, 114]. Figure 16 extracted from the former paper shows how lubricant filtration can have a significant effect on the fatigue life of bearings. The work indicated that wear debris from some other source may become entrained into the lubricated contacts and indent the bearing surfaces, giving rise to further failure.
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They change the oil and diff fluid on M cars.
You really want to compare the FF between M and non-M cars.
Patman
Staff member
My original question isn’t even about doing an early oil change at all. It’s about if anyone is using a break in oil. You seem to have forgotten that…
Thanks for all that. I'll spend some time later today looking it over, but first glance tells me that there's some good info here, something at least worth thinking about. Again, Thanks!
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Where does bmw come up with this mythical 1200 mile rule. Only thing I can say is they seen many failure rates at or around that mileage that they are doing this. Wouldn’t leave me feeling fuzzy all over. 1st off I wouldn’t be romping on the vehicle for the first 1000-1500 miles all GM says is to take it easy on the vette for the first 1500 miles.
Iirc BMW did this for decades with all cars and then only for M-cars starting in the late 1990's when free scheduled maintenance became a thing. M-car owners are made to feel special.
Carlostrece
$100 Site Donor 2025
You seem unreasonably hostile. I don't know what that's about. You could have just stated your opinion once and left it at that, as a reasonable person would have done. Have your opinion, do whatever with your car. We'll do the same.You're confusing "policy" with "opinion".
Again, so what ? Prove the long-term implications.
And you automatically blame it on NOT doing early oil changes ?
I don't care if you do it or don't do it. My argument is there's no proof it makes a difference. Almost no automaker recommends it either, but I guess we're to magically believe that these engines will squeak by long enough to make it out of warranty, right, then fail ?
You're mistaken. The 'vette is programmed to limit revs and power for the first 500 miles. Initially, the engine is limited to 4,500 rpm for the first 500 miles. Once the break-in period is complete, the redline and full power become available. I've seen that both on Jay Leno's Garage and Chris Sullivan's YouTube channel.
Click here to see the transition.
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Sadly I cannot find the Blackstone PDF from 2008 since it was on an email service that is defunct and I never archived it. Either way, you can go find modern examples on Bimmerpost and they are all some random LL-04 / LL-12FE etc factory fill.
Oh and deactivate running in check is just resetting the on board computer warning. I watched the tech do my M2 comp, there's nothing interesting done. I have a BMW ICOM Next A and ISTA+, anything interesting is done in different parts of the software and is quite invasive.
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Pretty sure Ford does on the GT350. I had this discussion with Ford when picking up a new GT350 for a long road trip. That is the flat plane crank engine that came out in 2016, with the different firing order than the regular Mustang V8. I asked to have the oil changed when I picked it up with 15 miles on it. They said no. The goal was a special break in oil. As an engine builder, my goal was to break it in my way that had worked well in the racing world and start with most of the dust and assembly junk out. The schedule called for hitting the road from West Coast to East so I wanted to start it right hitting it hard around town, then switch to final oil. The battle went on for a day and in the end they said you change the oil and we'll void the warranty. I was an engineer at GM so he was kind enough to call up the ladder with my plan. they came back with the application they use on the cylinder walls and why they wanted time to seat things their way. The sound of that engine was better therapy than any doctor's couch.
That's pretty much exactly what they told me when I got my Ridgeline back in September. Use full synthetic oil, and they made a deliberate point of telling me not to change it early and to follow the Maintenance Minder for the first oil change. The manual just says:
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