What Happens When Oil Changes Are Ignored, Poor Care?

[ZeeOSix]

So often the car that is dying early is written off because of a lack of proper oil changes. What happens? There is evidence that there is LESS wear with extened oil changes.

Certainly the oil oxidatively thickens increasing the MOFT. So wear should go down. The longer you run, the thicker the oil, the thicker the MOFT, ultimate wear control according to some. Wear should be zero.

What is wearing out and why?

Ali

Alot more to it than that. When oil is ran too long and breaks down, so does the engine protection. When the AW/AF additives go away, so does some of the wear protection. Then there's the neglect factor where some people never check the oil level and it gets to the point of inadequate lubrication situations. That wears and smokes engines pretty fast.

 

[ZeeOSix]

Hmmm I never heard of less wear with extended changes.............

There has been some research on that, and said that the longer the OCI (up to a point), the better a AF/AW tribofilm may exist, and that a fresh oil change can strip some of that wear protective tribofilm away until the new oil can build it back up.

 

[ZeeOSix]

There is only one viable way to rate engine wear, and that is disassembly and careful measurement. In particular, using very specific tools such as an scanning electron microscope, to measure incredibly minuscule rates of wear of specific components. Scientific methods are required.

That's not the only way. This is a much better way, but obviously not something anyone here could conduct.

https://www.swri.org/press-release/swri-adds-unique-efficient-engine-wear-testing-rig

 

[ZeeOSix]

It is easy to discern the industry professional we have on board regardless of what industry or trade to know their Knowledge, opinion and skill is valid. Again I thank our professionals for their inputs.

Did you noticed his comment: "The fact is, circulating dirty and diluted oil increases wear rates ..."

 

[ZeeOSix]

When you need special equipment just to measure "incredibly miniscule rates of wear" at all, it's pretty much a nothingburger as long as the engine runs fine.

I've seen some pretty worn out engines that still "runs fine".

 

[leadcounsel]

So often the car that is dying early is written off because of a lack of proper oil changes. What happens? There is evidence that there is LESS wear with extened oil changes.

Certainly the oil oxidatively thickens increasing the MOFT. So wear should go down. The longer you run, the thicker the oil, the thicker the MOFT, ultimate wear control according to some. Wear should be zero.

What is wearing out and why?

Ali

So, then how does sludge form?
How does wear occur? Is old worn out oil is somehow improved over new oil? Seems to me it stands to reason new oil would be inherently better.

 

[FishFry]

I've seen some pretty worn out engines that still "runs fine".

Running fine (without air quotes) is all I want from an engine - what's wrong with that?

 

[ZeeOSix]

Running fine (without air quotes) is all I want from an engine - what's wrong with that?

"Running fine" doesn't give any real indication of how worn the engine is. But if it gets you from point A to point B then guess that's all the matters.

 

[4WD]

Seems when counting on rebound viscosity from oxidative thickening - one would still need HTHS data on the used oil

 

[kschachn]

Seems when counting on rebound viscosity from oxidative thickening - one would still need HTHS data on the used oil

One would also need to understand what that oxidation can ultimately cause.

 

[BMWTurboDzl]

So often the car that is dying early is written off because of a lack of proper oil changes. What happens?

Excessive oil consumption (i.e down on power and MPG).
Running issues revolving around the VVT system.

I suppose technically you'd never have to change the oil on an engine because it would burn so much oil that you'd constantly have to top it off every 1-3k miles and perhaps only need to change the filter every 6 months of so.

 

[loneryder]

So often the car that is dying early is written off because of a lack of proper oil changes. What happens? There is evidence that there is LESS wear with extened oil changes.

Certainly the oil oxidatively thickens increasing the MOFT. So wear should go down. The longer you run, the thicker the oil, the thicker the MOFT, ultimate wear control according to some. Wear should be zero.

What is wearing out and why?

Ali

The next owner is screwed.

 

[4WD]

One would also need to understand what that oxidation can ultimately cause.

Sure - can actually go extreme at any point - hence the disclaimer “counting on“ (IMO) a false viscosity …
I have experienced what I believe to be extreme oxidation (early on) - and would describe it as thixotropic …

 

[FishFry]

So often the car that is dying early is written off because of a lack of proper oil changes. What happens? There is evidence that there is LESS wear with extened oil changes.

Well as long as you don't let her run out of oil (just topping it off when needed) pretty much nothing happens.
Topping the oil off over the years is like a very slow, but steady oil change.
I'm think no engine ever died., behause the oil was "too old" - more like from: "there was not enough oil anymore".

Of course there are variables, like if you drive just short distances, and the oil never has a chance to get really hot for a while, or if you redline it all the time etc. - but under "normal" conditions, no engine will die from "old oil".

Frank

 

[kschachn]

Is this in reference to the Ford SAE study 2007-01-4133" : https://www.sae.org/publications/technical-papers/content/2007-01-4133/

"In one of our previous studies it was observed that engine oil samples collected from fleet vehicles after 12,000 mile drain interval showed 10-15 % lower friction and more importantly, an order of magnitude lower wear rate than those of fresh oils."

"As in the previous study, the results showed that the aged engine oils provide lower friction and much improved wear protection capability. These improvements were observed as early as the 3000 mile drain interval and continued to the 15000 mile drain interval. The composition of tribochemical films formed on the surface with the 3000 mile drain interval is similar to that formed with the 12000 mile drain interval as seen before. These findings could be an enabler for achieving longer drain interval although several other factors must to be considered."

And as I noted that is a very flawed study, or perhaps very flawed conclusions. Check out this long thread and especially the later comments by user Shannow:

https://bobistheoilguy.com/forums/threads/changing-your-oil-too-often-will-harm-your-engine.132462/

 

[OVERKILL]

Well as long as you don't let her run out of oil (just topping it off when needed) pretty much nothing happens.
Topping the oil off over the years is like a very slow, but steady oil change.
I'm think no engine ever died., behause the oil was "too old" - more like from: "there was not enough oil anymore".

Of course there are variables, like if you drive just short distances, and the oil never has a chance to get really hot for a while, or if you redline it all the time etc. - but under "normal" conditions, no engine will die from "old oil".

Frank

You'll need to define "nothing happens" here.

When the additive package is depleted; when dispersants and detergents can no longer do their job and hold contaminants in suspension, those products lay down on surfaces and form varnish, sludge or lacquer. If you continue doing this, any new contaminants never even make it to the suspended stage, they just immediate accumulate on existing deposits and these build-up.

The ring land area will be one of the first to suffer, so oil control will start to be negatively impacted, resulting in consumption, so then you are "topping up" more frequently.

I've actually seen an engine or two "maintained" in this fashion, both were SBC's in GM 1500's (one was a Chev, the other a GMC) and they had about 3" of tar-black sludge in the valve covers with little pockets where the rockers were. Oil was checked, and "topped up" but never changed.

When I was in school I worked with a guy (he was one of the managers) that had a 95 F-150 with a 302 that was also invested in this "philosophy". Just adding oil "as it needed it", thought oil changes were a scam. Never got to see inside the valve covers on that one, but given what I've seen on 302's that received poor maintenance, I'm going to suspect it looked a lot like those SBC's. Super nice guy, but certainly on the left side of the bell curve.

 

[Greasymechtech]

I've seen sumps run out oil. If the owner simply topped it off regularly, there engine might still be running.

Oxidation/nitration and no filtration doesn't help.

I don't subscribe to the 'less wear' with aged oil theory.

 

[BMWTurboDzl]

I've actually seen an engine or two "maintained" in this fashion, both were SBC's in GM 1500's (one was a Chev, the other a GMC) and they had about 3" of tar-black sludge in the valve covers with little pockets where the rockers were. Oil was checked, and "topped up" but never changed.

How many miles?

 

[FishFry]

Well, how many of you have actually driven a car over 100,000 miles without an oil or filter change, just topping off?

I have (and still do).

So I guess I'm one of the few guys here (maybe even the only one - who knows) with actual hands on - real world experience in this over several years.
So how is it possible, that I don't see exzessive oil consumption, bad mileage, power loss, no sludge and all that other stuff I should see on my engine?

And yes - I know that this is a highly controversial thing in a forum, where almost everybody is seeing oil changes (with boutique oils) after 5000 miles, as best practice. My theory is, that it has to do with how much you drive at high oil temperatures. I do a lot of long distance driving, and I think that makes quite a difference, to the guy who got a - les than half an hour - drive around town each day. But maybe it doesn't - I don't know.

Frank

 

[kschachn]

Well, how many of you have actually driven a car over 100,000 miles without an oil or filter change, just topping off?

I have (and still do).

So I guess I'm one of the few guys here (maybe even the only one - who knows) with actual hands on - real world experience in this over several years.
So how is it possible, that I don't see exzessive oil consumption, bad mileage, power loss, and all that other stuff I should see on my engine?

And why are we supposed to believe that?