Asked a Honda engineer about the factory fill and whether there was any benefit to keeping it in longer

[qingcong]

The question keeps popping up about whether there is something special about the factory fill where it's better to keep it in until MM reads 15% or if it's totally okay to change it out early. There's a lot of opinions but not much definitive information. Honda corporate just gives you the 15% MM answer which doesn't answer what we want to know. I searched linkedin for Honda engine engineers and found a guy who was actually willing to engage in this geeky nonsense.

TLDR: Yes, they do use a special moly assembly lube, but it appears Honda engineers use this lube for initial startup and not for any sort of long term engine seating as some of us have been led to believe, so according to this guy Honda engineers are not aware of any difference between keeping the assembly mix in vs changing it out early.

 

[PointByPatrol]

Thanks for this! I think that settles it for everyone!

 

[ToddR]

Agreed! No magic elixir!

 

[evlsmurf]

Is he also alluding that there is no need to do the 1k mile break-in period?

 

[qingcong]

Is he also alluding that there is no need to do the 1k mile break-in period?

That's not what I gather from reading it. He says they do a break in test for 3 hours and after the break in test, there's no measurable difference between if they used a moly lube or not. It doesn't mean the break in is unnecessary.

 

[evlsmurf]

That's not what I gather from reading it. He says they do a break in test for 3 hours and after the break in test, there's no measurable difference between if they used a moly lube or not. It doesn't mean the break in is unnecessary.

Aight. I would be curious to know his thoughts on that...

 

[qingcong]

Break-in is definitive. There's videos/articles all over that discuss how break-in works. Savagegeese had a video where some Corvette engineers talked about the break-in process. It's usually within the first 100 miles, not 600 or 1000, but it's still a real thing.

 

[Gansan]

He did say:

So, is it required to "let it run its course", no, but doing a oil change earlier won't improve nor hurt anything.

So on one hand you can conclude that it's fine to change your oil early because the moly has done its job by X hundred miles, but on the other hand you can also argue that he is saying changing won't help either and you're just wasting time and money.

 

[J_D]

From what I understood he isn’t saying each engine is run for 3 hours and then tested in the production lines.

When they are benchmarking the engine design before release they do that to make sure the process is good and all is well.

 

[CVCC]

Thanks for the info. This is essentially the same info I got about 15 years ago. I do early oil changes just to check if my engine is making metal. So far I've been lucky on every new car purchased since 2007. Had I found an excessive amount of metal in either the oil or filter I'd call the dealer. Let them pull the pan and see what else is in there.

 

[Hiro-san]

Great find. Thanks for sharing the information.

 

[CTR39322]

This is somewhat related, I recently got a Honda lawnmower. I changed the oil after 1 hour of use and I could actually see metal particles in the oil.

 

[jtlctr]

Great info, thank you! Great idea finding this guy on Linkedin! I've been wondering about this too as I'm getting ready to do my first oil change before 2k. I figured the factory fill didn't need to stay in for very long. Now if I could only decide on which grade and brand of oil to use.

OCD sucks

 

[TypeRD]

Is he also alluding that there is no need to do the 1k mile break-in period?

It’s 1000 kms (~620 mi). It is recommended in some owner’s manuals (EU and Japan at least), but does not appear in the in the US owner’s manual. No one knows why, but there’s definitely some weird info omissions / inconsistencies in the US manuals. As such, the general recommendation is to follow the break-in period (listed in those other manuals). It can’t hurt, so may as well be patient and do it. ?

 

[TypeRD]

He did say:



So on one hand you can conclude that it's fine to change your oil early because the moly has done its job by X hundred miles, but on the other hand you can also argue that he is saying changing won't help either and you're just wasting time and money.

There’s no argument. He literally says “doing an oil change earlier won’t hurt nor improve anything.” This means, if you want to do it early, cool! If you want to wait and follow the MM or 1 yr interval, cool!

I think this tracks with the general recommendation that many here have adopted : Do the break-in 1000 kms, then change the oil whenever works best for your driving habits, environment factors, and/or preference.

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