Is there a limit to how much wear metal oil can hold?

[Santo Fontana]

The subject says it all. At some point will the oil become 'full' of metal and not be able to hold any more, therefore scewing the results of a UOA?

Can the contaminating metals fall out after a period of time?

Does an oil with more ppm of wear metals in it cause more wear to the engine?

Sorry if these questions have been asked before, I was sure they had but I had no success searching.

Thanks!

 

[Robbie Alexander]

Yes, there is a limit and it can SKEW the UOA results. Now, people like Terry I suppose if I understand him correctly CAN tell from an UOA even if this happens, at least even if theres sludge build up... He can't share this secret information because of his business depends upon it. If I got it wrong, well That's my understanding.

With Additives they can only be a certain amount too, after a certain level, the oil will not hold them too.

Interesting though to ponder unless someone has RAW data... How the breakdown of the oil affects this. If the Oil is sheered down, is there any change? I would suppose, but thats a guess.
If the oil heats up and gets too thin, I suppose there as well...

I do know with Many many back to back extended drains and dependant upon the length or severity, the oil can cause sludge, and it is possible to still show good wear numbers or least passing numbers and still have sludge building...

As far as PPM in the oil causing more wear. I would say theres gonna be possible debate here.
In general Yes, between two equal oils, IMHO.

Now though take through your thoughts for a moment if you will, a SUPER GOOD oil and a Common oil... If, IMO the super good oil CAN KEEP more suspended there will be less wear because of the suspension and the additives and other oil property. On the same token, the super good oil is most likely going to take much longer to build up too.

I too would like to know the limits PPM wise of oil, & of additives, & their relationship depletion wise.

 

[Santo Fontana]

Thanks for the info, Robbie. To be honest Im surprised no one else has responded.

I would love to extend my drains as far as possible, but not at the expense of messing up my uoa results.

 

[Doug Hillary]

Hi,
this is indeed an interesting point

In commercial automotive equipment it is common for Manufacturers to set wear metal limits

For Detroit Diesel Series 60 engines the limits are/were:
Iron;
Marine 2 cycle(53/71/92 series engines ) =250ppm
Non Marine 2 cycle( above series engines )=150ppm
Series 60 4 cycle engines =150ppm

Copper;
Above series 2 cycle engines =25ppm
Series 60 4 cycle engines =30ppm

Eaton Drive Axles ( document from 1993 ):
Replace lube OR Monitor;
Iron =1000ppm
Copper =120ppm
Chromium =5ppm
Aluminium =80ppm

Replace lube AND Monitor;
Iron =1500ppm
Copper =250ppm
Chromium =10ppm
Aluminium =150ppm

This shows that Manufacturers do have meaningful data - they do not generally broadcast it

I have never reached the l50ppm load of Iron in the DD 60 Series engines even at the 100kkms (62k miles) OC point. The highest reading we have recorded at the OC point has been about 140ppm
This particular engine has now done about 1m kkms (620k miles ) and has had an average oil consumption of 1ltr/6000kms to date

Regards
Doug

 

[Roger]

I think it is a good question, and one that doesn't appear to have had much discussion.

What is the carrying capacity of total oil contamination before the sheer number of particles start doing damage even if the wear rates are constant or low? And how do you measure it? For example, if iron wear is 3ppm/1000 miles at 3,000 miles, there would be a total level of 15 parts of iron per million in the oil. If it declines to 2.5 ppm/1000 at 6,000 miles, the total iron content in the oil would rise to 25 ppm. And say, the ppm/1000 mile rate declines to 2.0 at 9,000 miles duration , it would be 30 ppm total iron.

The Synthetic Oil Life Study illustrated that wear rates decline as oil ages. I've seen the same trend with UOA's posted here. I've summarized a group of Mobil 1 5W30 reports that show 2.68 ppm/1000 for iron on ave. oil changes of 4,635 miles. On changes that average 9,973 miles, reported iron runs 1.37 ppm/1000 for that same M1 5W30 viscosity. While the wear rate is cut in half, the total accumulation of iron in the oil is about 10% higher. So I guess the basic question is, how long can you continue running with dirtier?

 

[Robbie Alexander]

quote:

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Originally posted by Santo Fontana:
Thanks for the info, Robbie. To be honest Im surprised no one else has responded.

I would love to extend my drains as far as possible, but not at the expense of messing up my uoa results.

---

Me too. That's why I have set my TBN and other limits flagged for myself a lot less than I need to in general. It's "okay" to go over once and awhile or at least on one item, but when there two or three I get more concerned.

As far as you are concerned. If I were you, I'd run one or two back to back, as far as possible.
Then I would find the OUTER LIMITS of that oil and place a reasonable limit between the normal drain and the outer limit... If for instance, the normal drain with a dino for your car in the MFG book is 5000 for "normal" and you are "normal", and you find that through UOA's you can get to 10K safely but wouldn't want to push it to the limits.... I would back off someplace in the middle for all future drains. Then I would do a light flush or a VERY short OCI (maybe VERY VERY short) and get back into the normal and "new extended" drain... Always sample when you Change oil to monitor.

What I do and I may be wrong, but I place or figure all my Drains at say the 30K or 40K or 50-60K level, whatever makes cents or sense to you

. Example, PPM is at 5.1 for iron... and drain is at 4636 miles so 5.1/4636=0.001100086 then * 30000=33.00258844, I see that I'm still in the safe zone based on the MAX amount of PPM in there... I don't have any education, I just go by my gut! This is not linear abut I act like it is, mainly with iron, because although it can bounce up or down, it usually tracks with MILES... I still do the same to all other metals. For me if I know I don't want
Tin to even reach 10 or 5 or whatever, I'll do this... keep it fixed though, but for instance if Copper always tracks high, you can adjust to say 20K or it could track real low, then I go to say 60K... anyway when you see these numbers go up or SPIKE, the you know somethings up... Like I said I have no training in any of this, I just fly by the seat of my pants and GUESS based on what the data means to me... I may be 1000000% wrong!

Anyway the way I see it it's like the little trick I pulled on my dad when I was young asking him instead of giving me 2.00 a week for some chores, to just pay me a Cent the first of the month, and double it every day in the month and repeat the same next month... anyway my point is all these little numbers add up a lot more when there is a constant factor (large size) behind it all.

---
Doug:
What are these numbers called. This thing for commercial use such things... Where can I get that data for my Tacoma?

 

[Doug Hillary]

Hi,
sorry for a little error in my previous post

"For Detroit Diesel Series 60 engines...."
should have read;
"For Detroit Diesel engines...."

Robbie - I am not sure how you could obtain such wear metal data from non "Commercial" equipment suppliers
A letter to the Manufacturer's Head Office may set you off on the right direction

Regards

 

[heyjay]

As Doug mentioned, commercial customers expect and DEMAND to know operating limits before changing the oil or expecting problems.

Why? It's not just the huge cost of a Cummins or Detroit Diesel motor, though +$25,000 is a GOOD incentive. It also has to do with servicing.

Whenever a heavy tractor is in the shop, it's losing money. It has to be on the road to make money. So the longer you keep it on the road, the better.

Sump capacities are quite huge too. Cars and trucks (Utes in Austraillia) might have a 6 litre sump max. Large DDA or Cummins motors can hold 30-60 litres. That is a messy and time consumming oil change procedure.

The best way to keep wear metals out of the oil so not to worry about it is to run bypass oil filters and especially centrifugal bypass oil systems.

I'm sure Doug Hillary can relate some horror stories on what he has found after cleaning out the centrifuge. Sometimes that crud is hard as cement!

 

[Al]

The other issue that is not adressed in the oil analysis joe sixpack gets done is, the particle count and size of those particles. Thats a whole other sience. For instance you could have 100 ppm of iron at 15 microns that could be much better then 50 ppm of iron at 30 microns.

 

[Santo Fontana]

Al, what is the range in microns a uoa picks up? If a full flow filters down to 20 microns (is that accurate?) and a uoa only covers 0-5, then there would be a gap of missing information. I think the range a uoa covers is probably a good representation though.

Roger, the fact that oil does better over time is surprising to me. It makes me think that the metal could be settling out of the oil, or the oil cant pick up the wear metals fast enough.

Doug, thanks for that info. If manufacturers are willing to see over 100ppm of iron for example, it leads me to believe I am wrong on my last point. I probably wouldnt reach that level on anything for about 100,000 miles.

 

[Robbie Alexander]

quote:

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Originally posted by Doug Hillary:
-*-*-*
Robbie - I am not sure how you could obtain such wear metal data from non "Commercial" equipment suppliers
A letter to the Manufacturer's Head Office may set you off on the right direction

Regards

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Yeah, I know it exists. But where and how much. All I need is a photocopy of my make and model... I'll be able to figure from there how I want my set-up to run.

 

[Santo Fontana]

>>>>>

Id like to here some more thoughts on this topic.

 

[Drstressor]

Most "normal" wear metal particles are under a micron. The standard method used to measure wear metal levels does not detect particles larger that a few microns. Only particle counting can detect larger wear particles with any degree of efficiency. Keep in mind that the human eye can only resolve down to about 50 microns. So if you can see scoring on an engine part, imagine the size of the metal particles that flaked off. Most of this type of metal will end up in the filter.

 

[Roger]

I bought that SAE paper cited in the oil study. The authors of that paper felt that aged oil wear rates slow down for basically 2 reasons. One, the antiwear film of used oil might be better than new oil additives as the result of high temperature oxidation in aged oils, and secondly, that the barrier film of the previous oil is slowly replaced by new films of the new oil. Once this replacement process is done (within the 1st few thousands of miles???) engine wear rates decrease significantly. That's their theory...intriguing. And some data tends to show real world evidence of those ideas.

However, this doesn't address your original question. I wonder if part of that answer may be that we are overly concerned about minute differences in wear rates that may not amount to a hill of beans over the lifetime of the engine anyway. If you check the "What is Oil Analysis" section of Bob's home page, you'll eventually see information about average acceptable levels of wear metals. I presume they are somewhat accurate numbers and not "illustrative." If they are representative of what Bob has truely seen from all his years of experience, they are a lot higher than what we are accustomed to see in the UOA section. Acceptable iron rates of 100 to 200 ppm. Lead: 40 to 100 ppm. Heck, it took that Camaro in the oil study 18,000 miles to approach those total lead numbers and never got past the half way mark on the iron. So, I guess I'm speculating that while engine wear continues at a diminished pace, the total accumulation of those wear metals at least "do no harm" if they are still within "acceptable" levels.

 

[Robbie Alexander]

quote:

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Originally posted by Santo Fontana:
>>>>>

Id like to here some more thoughts on this topic.

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Well I was on the Cell phone today for about 1 Hour on one call and about another 1/3 hour on a couple other calls to Toyota about this issue.

You'd be surprised what they said.
Although they could not locate any data for me
The NUTSHELL was
"well Sir, it's the oil that determines the PPM not the engine, the engine if properly maintained will always wear the same, but the OIL will decide the rates of wear"-> fairly close to his exact words, sorry didn't have a recorder, I was on there for some time... On the last call about 30 minutes, I had not on the line, but another man contact THEIR (Toyotas) TECH department and the guy didn't know of a source of the WEAR # issue for my truck. I'd like to know!

 

[dickwells]

This discussion plays right into the article I read in Mechanix illustrated many years ago. They found that a new engine broke in faster and cooler if used oil was put in it for breakin. Thats why I try to extend my first oil change out to the limit rather than giving a new engine a 500 mile change and then thousand mile changes like some on this board do.

 

[Patman]

quote:

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Originally posted by dickwells:
This discussion plays right into the article I read in Mechanix illustrated many years ago. They found that a new engine broke in faster and cooler if used oil was put in it for breakin. Thats why I try to extend my first oil change out to the limit rather than giving a new engine a 500 mile change and then thousand mile changes like some on this board do.

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I'm beginning to think this way too. If I get a new car, it's first oil change will not be at 500 miles or less like I always did in the past, but instead I'll take it out to 3k.

The exception would be if I had an engine rebuilt though, since these usually end up with a lot of assembly lube and the likes into your oil. In a case like this I'd do quite a few oil changes before the 3k mark.

 

[therion]

quote:

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Originally posted by Patman:

quote:

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Originally posted by dickwells:
This discussion plays right into the article I read in Mechanix illustrated many years ago. They found that a new engine broke in faster and cooler if used oil was put in it for breakin. Thats why I try to extend my first oil change out to the limit rather than giving a new engine a 500 mile change and then thousand mile changes like some on this board do.

---

I'm beginning to think this way too. If I get a new car, it's first oil change will not be at 500 miles or less like I always did in the past, but instead I'll take it out to 3k.

The exception would be if I had an engine rebuilt though, since these usually end up with a lot of assembly lube and the likes into your oil. In a case like this I'd do quite a few oil changes before the 3k mark.

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On my Audi A4 1.8T, i waited unto 5,000miles before i changed my factory fill over to Amsoil Series 2000 along with a SuperDuty filter.

 

[pete643]

When I bought my Jetta with the VR6 the dealer said not to change the factory fill oil until the car had 7,500 miles. That is what I did, and it was probably the right thing to do, as the car now has close to 245,000 trouble free miles on the engine.

 

[Robbie Alexander]

quote:

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Originally posted by dickwells:
-*-*a new engine broke in faster and cooler if used oil was put in it for breakin.-*-*

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Hummmm, Anyone want me to send them my used oil>?

....
To a certain degree I may lean there but not how you may think.
As long as there is proper and EVEN wear to the point that all rings and such are TIGHT, totally flush, etc. then I wouldn't care if SAND was used.
The whole thing for me and my thinking is EVEN WEAR and proper seating of ALL moving parts.

Now, back to the question with a twist...
At what maximum but safe FLAG level may ALL the elemental wear metals be RUN up to; Before there is EXCESS WEAR, and BEFORE there is UNEVEN wear ie where a part is wearing faster than the others...
Then, when all the metals are evenly wearing (properly or in balance), HOW much PPM of ALL wear metals can a GOOD sample of oil hold, AND how many PPM of WEAR metals can a poor or sheered or diluted oil sample hold (say 2% fuel or sheer 2 points, etceteras)????????????????????????????????????????????????????????????????????????????????????????