2015 BMW N20 X1 UOA 5K MILES NON-EURO OIL: ROUND 2

I have found the opposite to be true. BMW engines, regardless of type, year etc. seem to sludge up more than others I have worked on and own. I am not talking about just my experience either, I know retired techs who have seen this also, plus the internet shows multiple examples. The highly evolved service indicator system should be able to compensate for abusive scenarios, and pull back OCI accordingly.



My position is this:

BMW used the sulphur excuse for their V8 engine problems in the 90s, which may have actually have been the case. I don't buy it for this.

Somewhere in that firm they have decided on a philosophy of long drains and lifetime fills.

Lifetime fills in GM and Aisin built transmissions that other firms use with more reasonable (realistic) intervals.

I love BMW and think their cars are excellent. But, they do make mistakes, which somehow, they never admit to.

For the enthusiast, BMW recommendations should be considered to be for a different purpose than solely vehicle longevity.

I mean fluid type as well as interval in the above statement.

When people only recommend going with a fluid that meets the cert, I think that is certainly a safe bet, but is also not the end of the discussion, especially where BMW is concerned.
Sulphur wasn't an excuse but a fact. It was a metallurgical issue.

BMW engines don't develop sludge unless the oil hasn't been changed on time or the wrong oil was used. IMO there was less margin for error on a 15k interval. IMO BMW also expected the N20 to make the same power as the NA I6 it replaced so the demands of the TGDI I4 were higher.
 
I have found the opposite to be true. BMW engines, regardless of type, year etc. seem to sludge up more than others I have worked on and own. I am not talking about just my experience either, I know retired techs who have seen this also, plus the internet shows multiple examples. The highly evolved service indicator system should be able to compensate for abusive scenarios, and pull back OCI accordingly.



My position is this:

BMW used the sulphur excuse for their V8 engine problems in the 90s, which may have actually have been the case. I don't buy it for this.

Somewhere in that firm they have decided on a philosophy of long drains and lifetime fills.

Lifetime fills in GM, ZF, and Aisin built transmissions that other firms use with more reasonable (realistic) intervals.

I love BMW and think their cars are excellent. But, they do make mistakes, which somehow, they never admit to.

For the enthusiast, BMW recommendations should be considered to be for a different purpose than solely vehicle longevity.

I mean fluid type as well as interval in the above statement.

When people only recommend going with a fluid that meets the cert, I think that is certainly a safe bet, but is also not the end of the discussion, especially where BMW is concerned.


And for myself, for disclosure, I have a bias toward experiment. I usually try the cert, and then begin to use something else, maybe. Sometimes its not any radical shift, for engine or transmission, sometimes it somewhat is, like 20w50 in a 5w20 spec engine. (Rotary).
The reason they sludge is neglect. I haven’t seen any reasonably maintained that sludge.
They run hot, especially N generation engines with variable temperature temperature settings.
When people recommend BMW approved oils, those are also oils that are more stout than your average off the shelf “full synthetic “ oils.
Of course you can experiment with whatever you won’t. That still doesn’t change outcome you presented in UOA. I do experimenting for living, and it is not always outcome I think I will get.
 
Sulphur wasn't an excuse but a fact. It was a metallurgical issue.

BMW engines don't develop sludge unless the oil hasn't been changed on time or the wrong oil was used. IMO there was less margin for error on a 15k interval. IMO BMW also expected the N20 to make the same power as the NA I6 it replaced so the demands of the TGDI I4 were higher.
Well, it was a factual excuse. The actual problem was bad engineering and testing for the largest BMW market in the world at that time. The coating BMW used was not new, their process was though, and that was why it was susceptible to fuel acid etching and erosion. They didn't know about American gas in 1991? That's why the long drain Sulphur excuse doesn't hold water with me. They did it again? Really?

Also, the vehicles I have seen and the mechanics I have spoken to have seen sludge in warranty or just outside of warranty, in under 100k vehicles. That means dealer maintained or just outside of dealer maintenance. The service indicator is supposed to accurately adjust for driving style, regardless of who is doing the oil changes.

Also, nobody addressed the lifetime transmission fills issue I raised.

I'm not beating on this, I am OK to differ and let it lie. But maybe put aside your BMW biases (we all have them, not meant by me to be a derogatory statement by any means) and really consider that BMW get it wrong sometimes, and they will quote intervals that are not in line with what an enthusiast would prefer. That doesn't mean I am using that to justify my oil choice either. But, it is a consideration to bear in mind, even if its only at the back of mind.
 
Well, it was a factual excuse. The actual problem was bad engineering and testing for the largest BMW market in the world at that time. The coating BMW used was not new, their process was though, and that was why it was susceptible to fuel acid etching and erosion. They didn't know about American gas in 1991? That's why the long drain Sulphur excuse doesn't hold water with me. They did it again? Really?

Also, the vehicles I have seen and the mechanics I have spoken to have seen sludge in warranty or just outside of warranty, in under 100k vehicles. That means dealer maintained or just outside of dealer maintenance. The service indicator is supposed to accurately adjust for driving style, regardless of who is doing the oil changes.

Also, nobody addressed the lifetime transmission fills issue I raised.

I'm not beating on this, I am OK to differ and let it lie. But maybe put aside your BMW biases (we all have them, not meant by me to be a derogatory statement by any means) and really consider that BMW get it wrong sometimes, and they will quote intervals that are not in line with what an enthusiast would prefer. That doesn't mean I am using that to justify my oil choice either. But, it is a consideration to bear in mind, even if its only at the back of mind.
I think you're conflating the two. The Nikasil issue was a testing and engineering failure due to BMW not realizing that high sulphur levels in US and UK (yes, this was a thing in the UK as well) gasoline would cause cylinder wall etching. This issue pre-dates the LL98 and LL01 specifications btw and was during a time when long drains weren't really a thing. Steel liners were introduced around 1998.

Western europe moved to ULSD/ULSG around mid-2000's which is when LL04 was introduced. The US didn't completely phase in ULSG until around 2020.

Dealer maintained doesn't mean anything if the owner doesn't bring the car into the dealer on time.

As for lifetime ATF, while not as popular as motor oil UOAs there are a few around here on the ZF fluid at around 50k miles and the fluid is tested as having plenty of life in it which makes sense since ZF themselves said lifetime or 8 years unless the transmission is under constant high speeds, loads. They then recommended a change at around 55k-75k miles. Anecdotally AT failures on BMW's are rare unless there was a manufacturing defect at which time the failure occurred rather early or the vehicle was modified and/or tracked.
 
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Well, it was a factual excuse. The actual problem was bad engineering and testing for the largest BMW market in the world at that time. The coating BMW used was not new, their process was though, and that was why it was susceptible to fuel acid etching and erosion. They didn't know about American gas in 1991? That's why the long drain Sulphur excuse doesn't hold water with me. They did it again? Really?

Most European countries started limiting gasoline sulfur levels in the early 90s. It was lower than the US at the time the M60 engine was produced. The problem areas exactly correlated to the permitted sulfur levels in fuel. The western European levels in the mid-90s weren't as low as they are today but they were low enough.

I have a friend who owned a Nikasil E34 that had been in storage for most of its early life. He drove it in the mid-2010s until it was sold. It did not have compression problems, unlike my E34 before had the Alusil replacement engine. BMW's deposition process wasn't any different than anyone else's process such as Porsche (which also experienced problems). Not all Nikasil coatings were affected on all engines but the chemical process was and is well understood.
 
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I think you're conflating the two. The Nakasil issue was a testing and engineering failure due to BMW not realizing that high sulphur levels in US and UK (yes, this was a thing in the UK as well) gasoline would cause cylinder wall etching. This issue pre-dates the LL98 and LL01 specifications btw and was during a time when long drains weren't really a thing. Steel liners were introduced around 1998.

Western europe moved to ULSD/ULSG around mid-2000's which is when LL04 was introduced. The US didn't completely phase in ULSG until around 2020.

Dealer maintained doesn't mean anything if the owner doesn't bring the car into the dealer on time.

As for lifetime ATF, while not as popular as motor oil UOAs there are a few around here on the ZF fluid at around 50k miles and the fluid is tested as having plenty of life in it which makes sense since ZF themselves said lifetime or 8 years unless the transmission is under constant high speeds, loads. They then recommended a change at around 55k-75k miles. Anecdotally AT failures on BMW's are rare unless there was a manufacturing defect at which time the failure occurred rather early or the vehicle was modified and/or tracked.
And Nikasil was replaced with Alusil.
 
I think you're conflating the two. The Nikasil issue was a testing and engineering failure due to BMW not realizing that high sulphur levels in US and UK (yes, this was a thing in the UK as well) gasoline would cause cylinder wall etching. This issue pre-dates the LL98 and LL01 specifications btw and was during a time when long drains weren't really a thing. Steel liners were introduced around 1998.

Western europe moved to ULSD/ULSG around mid-2000's which is when LL04 was introduced. The US didn't completely phase in ULSG until around 2020.

Dealer maintained doesn't mean anything if the owner doesn't bring the car into the dealer on time.

As for lifetime ATF, while not as popular as motor oil UOAs there are a few around here on the ZF fluid at around 50k miles and the fluid is tested as having plenty of life in it which makes sense since ZF themselves said lifetime or 8 years unless the transmission is under constant high speeds, loads. They then recommended a change at around 55k-75k miles. Anecdotally AT failures on BMW's are rare unless there was a manufacturing defect at which time the failure occurred rather early or the vehicle was modified and/or tracked.
No, I am not conflating the two. Never mind. I am not able to convey my point.

And, since three responses from three different forum members later, nobody is understanding what I am saying, and giving coherent responses, I am willing to drop it. So, lets drop it.
 
Well, it was a factual excuse. The actual problem was bad engineering and testing for the largest BMW market in the world at that time. The coating BMW used was not new, their process was though, and that was why it was susceptible to fuel acid etching and erosion. They didn't know about American gas in 1991? That's why the long drain Sulphur excuse doesn't hold water with me. They did it again? Really?

Also, the vehicles I have seen and the mechanics I have spoken to have seen sludge in warranty or just outside of warranty, in under 100k vehicles. That means dealer maintained or just outside of dealer maintenance. The service indicator is supposed to accurately adjust for driving style, regardless of who is doing the oil changes.

Also, nobody addressed the lifetime transmission fills issue I raised.

I'm not beating on this, I am OK to differ and let it lie. But maybe put aside your BMW biases (we all have them, not meant by me to be a derogatory statement by any means) and really consider that BMW get it wrong sometimes, and they will quote intervals that are not in line with what an enthusiast would prefer. That doesn't mean I am using that to justify my oil choice either. But, it is a consideration to bear in mind, even if its only at the back of mind.
BMW develops engines with German approach to development not American.
V8 engines at that time were sold also in large numbers in Europe as well. All their cars and engines are developed that way.
The A/C issue in 70’s explains that the best.
 
Did the oil change tonight. Looks like it was over 8k on this OCI. Should be interesting. I will post a picture of the filter also.
 
BMW develops engines with German approach to development not American.
V8 engines at that time were sold also in large numbers in Europe as well. All their cars and engines are developed that way.
The A/C issue in 70’s explains that the best.
I am aware of that! I owned 2 e28s, both had the non-integrated AC system. The one I was driving (88 535) when I moved to AZ needed a lot of work to bring up to the task, including adding a second condenser in series, since the area allowed by the factory core support was too small.

The original point was that many manufacturers had the Nikasil process down pat when the V8s were being developed. It was not a new technology at that point. BMW did not test adequately and got their sums wrong. It happens.
 
BMW develops engines with German approach to development not American.
V8 engines at that time were sold also in large numbers in Europe as well. All their cars and engines are developed that way.
The A/C issue in 70’s explains that the best.
I am not sure they think it is wrong necessarily. Sulfur was an issue. A lot of N63 issues stem from their utilization by lease owners in the US. They don’t want to give up hot bay design even after some 15 years. They adjusted other stuff to make it work with Jane that drives 2 miles one way and likes redline out of driveway at -20 degrees.
 
I am not sure they think it is wrong necessarily. Sulfur was an issue. A lot of N63 issues stem from their utilization by lease owners in the US. They don’t want to give up hot bay design even after some 15 years. They adjusted other stuff to make it work with Jane that drives 2 miles one way and likes redline out of driveway at -20 degrees.
Its not Jane, it's Chanel. Get it right, man. ;)
 
I have found the opposite to be true. BMW engines, regardless of type, year etc. seem to sludge up more than others I have worked on and own. I am not talking about just my experience either, I know retired techs who have seen this also, plus the internet shows multiple examples. The highly evolved service indicator system should be able to compensate for abusive scenarios, and pull back OCI accordingly.
My son has a 2009 328i that was his DD prior to picking up a 2018 330i xDrive . The car has been run on BMW TPT 5W-30 or BMW TPT 0W-30 since new- with a minimum OCI of 15,000 miles/12 months; here's what it looked like at 108,000 miles:
1659892633515.png
 
My son has a 2009 328i that was his DD prior to picking up a 2018 330i xDrive .
Hold on, this is naturally aspirated straight-six non-turbo N53 engine. To be truly honest, kind of a really different animal to compare with N20.
I do not really think N20 will be that clean after 15K OCI even with BMW approved oil
 
Hold on, this is naturally aspirated straight-six non-turbo N53 engine. To be truly honest, kind of a really different animal to compare with N20.
I do not really think N20 will be that clean after 15K OCI even with BMW approved oil
Please note that I was replying to the following comment:
“I have found the opposite to be true. BMW engines, regardless of type, year etc. seem to sludge up more than others I have worked on and own.”
Context is everything.
 
My son has a 2009 328i that was his DD prior to picking up a 2018 330i xDrive . The car has been run on BMW TPT 5W-30 or BMW TPT 0W-30 since new- with a minimum OCI of 15,000 miles/12 months; here's what it looked like at 108,000 miles:
View attachment 111502
That engine definitely looks cleaner than my wife's N52, but I think you do have sludge forming (formed). The aluminum bars that hold the Valvetronic springs are a telltale to me. Your rear bar is cleaner than the front. (No, its not the lighting). That is exactly how my engine looked, but worse. If you took a fingernail and scraped that front bar, I think you would get a nice peel of goop. Underneath that bar is also a goop collector, the sludge on my wife's car was starting to show up in little pieces on the helper springs too. Also, I will bet you $5 that the 10mm bolt heads on the exhaust cam blocks have sludge in the recesses. And, this is the stuff you can see. To each his own, but a 15k oil change, or 15k plus, is not something I would be encouraged to personally persist in doing, and I try lots of things that counter convention. At 10k or (ideally) less, with the same oil, that engine would be spotless at that (low) mileage, in my opinion.
 
This is the latest sample. It shows 8k miles, but we lost track of the actual mileage. 8k is conservative, its likely over 8500, and maybe pushing 9k. I unwound the filter to take a picture of it, but there was no metal and no sludge. The filter was Mahle. I get small carbon/sludge particles in my wife's N52 filter every time after 5k changes of that engine which has visible sludge under the valve cover. I was expecting to see something in the filter, but there was nothing to report.

The Sample "BL" on the report is virgin oil. Unfortunately is is not from the same batch as the UOA. Sorry about the low quality, the PDF was password protected and I could not edit it. I will say OA definitely requires more of a brain commitment than BS to get a report done. My brain is being used in many other places, so a crappy scan will have to suffice this time.

What do you think?

1662392739723.png


Previous 5k mile report below. OA did not tie the two together on the new report.

1662393378396.jpg
 
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Am I reading that right? TBN is 0.74? I think you got every mile you could out of that run. Why did OA not flag this?
 
Well, fuel has come down but viscosity didn't go up, so that points to mechanical shear taking place. 18% viscosity loss in this most recent sample with 1.8% fuel, vs 17% with 3% fuel. Oxidation is also twice as high on the longer interval. Boron seems to be getting wiped-out, down significantly in the 5K sample and almost gone in the 8K one.

TBN is scary low if I'm interpreting that right.
 
Well, fuel has come down but viscosity didn't go up, so that points to mechanical shear taking place. 18% viscosity loss in this most recent sample with 1.8% fuel, vs 17% with 3% fuel. Oxidation is also twice as high on the longer interval. Boron seems to be getting wiped-out, down significantly in the 5K sample and almost gone in the 8K one.

TBN is scary low if I'm interpreting that right.
The Boron almost seems to be tracking with the TBN, which brings us back to what I brought up earlier in the thread. I'm sure this is not universal, but I looked at some of my old UOAs that included TBN and in most cases, they did track fairly closely. Obviously, oils that have a very high or very low starting Boron will not track as well.
 
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