Running in oil
Discussion
And by this I mean new oil being run in to achieve maximum performance, not a running in oil for a new engine...
I was talking to a guy on the weekend with impressive qualifications telling me I was wasting my money doing an interim (7500mile) oil change as the manufacturer recommended change was 15k and synthetic oils are designed to 50k (though he didn't mention the stopstart nature of my plug in hybrid and what effect that has given sometimes engine doesn't even warm up over a 30 mile run)
I've always gone to the trivial expense of a 50% of the way through oil change for peace of mind thinking it likely does some good but cannot do any harm.
He disagreed, drawing me a graph of 0-50k miles on X axis, 0-100% oil performance on Y axis. The graph didn't start at 100%, level then dropping towards the 50k, instead it started lower on Y then built up to 100% over first 1000 miles then stayed there until around 50k before dropping off again.
Apparently the early poor performance was caused by the chemicals that are added to keep it fresh in the bottle for however long it's on the shelf for. They burn off initially but reduce the performance of the oil as they do so.
Does anyone *know* about this? It was new to me and his background in engines and academia really made me think he knew what he was talking about. It would suggest changing at 7.5k would actually cause the engine more wear not less since it'd have to get through the initial "running in" period twice per oil change not once.
I appreciate oil discussions usually go off into "I've done this man and boy and therefore it's right" stuff, but I'd really like this thread reserved for people who know from genuine knowledge and science what they're talking about if possible, i.e. subject matter experts.
I was talking to a guy on the weekend with impressive qualifications telling me I was wasting my money doing an interim (7500mile) oil change as the manufacturer recommended change was 15k and synthetic oils are designed to 50k (though he didn't mention the stopstart nature of my plug in hybrid and what effect that has given sometimes engine doesn't even warm up over a 30 mile run)
I've always gone to the trivial expense of a 50% of the way through oil change for peace of mind thinking it likely does some good but cannot do any harm.
He disagreed, drawing me a graph of 0-50k miles on X axis, 0-100% oil performance on Y axis. The graph didn't start at 100%, level then dropping towards the 50k, instead it started lower on Y then built up to 100% over first 1000 miles then stayed there until around 50k before dropping off again.
Apparently the early poor performance was caused by the chemicals that are added to keep it fresh in the bottle for however long it's on the shelf for. They burn off initially but reduce the performance of the oil as they do so.
Does anyone *know* about this? It was new to me and his background in engines and academia really made me think he knew what he was talking about. It would suggest changing at 7.5k would actually cause the engine more wear not less since it'd have to get through the initial "running in" period twice per oil change not once.
I appreciate oil discussions usually go off into "I've done this man and boy and therefore it's right" stuff, but I'd really like this thread reserved for people who know from genuine knowledge and science what they're talking about if possible, i.e. subject matter experts.
Edited by supermono on Tuesday 5th January 18:21
A classic example of failing to read the OP properly. First of all I'm doing 7.5k oil changes, 50% through recommended 15k. Secondly this chap wasn't advocating 50k changes, rather he was just saying that from his university studies and industry experience (not a random bloke BTW) the oil companies were designing oils with a 50k theoretical life. This he suggested meant that the 15k wasn't stretching them.
And thirdly, my *actual* question for which you would need to be a subject matter expert to answer, was around this shelf life preserving chemical(s) he spoke about. These apparently take a short while to disperse hence reduce the initial oil performance.
I knew it was a minefield so I thought I was super clear, apparently I wasn't.
(@xjay1337 BTW as post came in between)
And thirdly, my *actual* question for which you would need to be a subject matter expert to answer, was around this shelf life preserving chemical(s) he spoke about. These apparently take a short while to disperse hence reduce the initial oil performance.
I knew it was a minefield so I thought I was super clear, apparently I wasn't.
(@xjay1337 BTW as post came in between)
PhillipM said:
What shelf life preserving chemical would be in there that the oil wouldn't already need for resisting oxidation whilst being pumped around at pressure at 90-130*c. Oxidation resistance and TBN to neutralise acid byproducts is a big thing in oils...
You're telling me it needs something special that only works in a sealed plastic bottle with a few CC of air in the top whilst sat stationary at 20c?
Well no I'm not telling anyone anything, I'm just asking if what I was told has any basis in reality.You're telling me it needs something special that only works in a sealed plastic bottle with a few CC of air in the top whilst sat stationary at 20c?
This chap has a degree in mechanical engineering specialising in oils. He described the test rigs etc and was certainly talking as a subject matter expert.
Forgive me but you're speaking as a bloke on the internet. Your opinion sounds reasonable but really I need someone who's got facts not opinions as I'm wanting to learn by asking the question
Forgive me but you're speaking as a bloke on the internet. Your opinion sounds reasonable but really I need someone who's got facts not opinions as I'm wanting to learn by asking the question
Thing is amongst blokes on the internet are a few extremely knowledgeable people, I was hoping to tap into that vein of knowledge.
You guys thinking I'm advocating a 50k oil change contrary to everything I said is really testament to how people don't read before answering.
Maybe someone who knows how oils are blended and who knows categorically whether or not there are compounds to preserve them in the bottle that reduce their efficacy in the engine, and maybe they'll answer this thread.
But I'm not very hopeful.
You guys thinking I'm advocating a 50k oil change contrary to everything I said is really testament to how people don't read before answering.
Maybe someone who knows how oils are blended and who knows categorically whether or not there are compounds to preserve them in the bottle that reduce their efficacy in the engine, and maybe they'll answer this thread.
But I'm not very hopeful.
I've had a response from an oil laboratory:
"Thank you for your email regarding premature changing of the lubricant, it has been pointed out before that oil is volatile in the first few thousand miles and then stabilises during which time if you keep changing the oil increase soot is produced,which may harm the engine (no proof at this stage) further to add quality oil contains phosphorus as an additive which boils initially after change so allowing this to settle is probably a good idea especially for gasoline/hybrid vehicles. most manufacturers will give an indication via ASSYST or similar programs when change servicing is required for oils. this is a guide but of you were to change earlier (not too early) then it cannot be harmful as oil stabilisation has proceeded and purpose of lubrication has been fulfilled."
So there you have it, turns out it was true after all.
"Thank you for your email regarding premature changing of the lubricant, it has been pointed out before that oil is volatile in the first few thousand miles and then stabilises during which time if you keep changing the oil increase soot is produced,which may harm the engine (no proof at this stage) further to add quality oil contains phosphorus as an additive which boils initially after change so allowing this to settle is probably a good idea especially for gasoline/hybrid vehicles. most manufacturers will give an indication via ASSYST or similar programs when change servicing is required for oils. this is a guide but of you were to change earlier (not too early) then it cannot be harmful as oil stabilisation has proceeded and purpose of lubrication has been fulfilled."
So there you have it, turns out it was true after all.
xjay1337 said:
OK, no-ones debating that there may be items in oil that stabilise it, we are talking about 50k service life.
Where's that?
Perhaps you should read my original post, the 50k was an irrelevant piece of data to illustrate the graph. Nobody at any point was advocating a 50k oil change -- not him, not me, not anybody.Where's that?
The question was around a potential running in period for oil -- like what it says in the title.
xjay1337 said:
Haha. It still makes me laugh you believe some random guy in real life with a preposterous idea instead of random blokes on the internet with logical ideas.
Out of interest did you make a decision one day that you now know everything and from now on anything new is laughable and preposterous?For me every day's a school day and it's fascinating to have "knowledge" challenged. Hey we're all different though
one eyed mick said:
There is too much bull poo on this if oil needs running in why is race oil changed as often as every 30/40 mile race ?
The information came from a professional within the oil industry working in a commercial laboratory. I assume your degree level education around oils and lubricants backed with your many years working daily analysing and formulating oils allows you to call that bull poo. Good for you.But as a lowly office worker, I have to go with the expert.
George111 said:
So are you saying that you believe oil takes 1000 miles to start working at full efficiency ?
No but I believe that it has additives which during the initial period of perhaps 1000 miles will burn off and potentially cause soot issues if you continually used fresh oil within a few hundred miles. But that's just what I've been told and I have no better source of information. Also it sounds rather too specific to have been made up.Gassing Station | Engines & Drivetrain | Top of Page | What's New | My Stuff