0W-40 and Potential Rod Bearing Wear....0W-50 on the Street?

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2,807
Location
High Tax Illinois
I don't know anything about these engines. But. Where is the oil pump? Is there a High Volume/High Pressure pump available? I would think a better oil pump would be the problem solver here.
 
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11,663
Location
Colorado Springs
I don't know anything about these engines. But. Where is the oil pump? Is there a High Volume/High Pressure pump available? I would think a better oil pump would be the problem solver here.
His specific question is not related to engines that have that problem.
The oil pump in those other engines I would say is adequate. Some of those engines had some problematic years not all, and different bearings were solution.
 
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11
Location
US
BMW high performance engines have had a near 20 year record of having rod bearing issues. In the pursuit of HP and minimizing internal friction, they have narrowed the bearing from the legacy rod bearing that didn't have any issues. There were also come clearance issues for a period form 2003-2013. This combined with the fact that the HP/cylinder continues to climb makes me nervous on my current engine, the S55 (M3/M4). The did increase the bearing width over the last two generations, but still isn't as wide as the older bearings. The factory oil recommended is a 0W-40, and I'm currently running the Castrol Edge 0W-40 A3/B4 oil.

I've seen a hand full of posts were rod bearings were already replaced at 30,000-60,000 miles with a lot higher wear that I would expect. I'm running this because during my initial research, this looked like it had a higher percent of group IV oil, where Mobil 1 0W-40 FS was group III. Not 100% sure since all of this is hard to pin down. My first oil analysis got lost, and I'm due for an oil change. I drive the car EXTREMELY hard, and eventually plan to modify it running E85 adding 150+ hp over the stock output.

Make sure you change the oil much more frequently if you use e85, it 'thins' out oil very quickly. Look at 3k changes. Doesnt look like anything is going to help with rod bearing issue anyway. However, you might try a left field approach using a oil additive like Lubegard and/or high friction modified oils with moly etc.
 

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45,303
Location
Ontario, Canada
"Castrol Edge 0W-40 A3/B4 oil is Group iv. Mobil 1 0W-40 FS was group III"
That is the wrong way round.

Nope, the current version of Castrol Edge 0w-40 A3/B4 is up to 50% PAO, whilst the current MSDS for M1 FS 0w-40 shows 10-20% PAO, 50-60% Group III:
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Messages
11,663
Location
Colorado Springs
Make sure you change the oil much more frequently if you use e85, it 'thins' out oil very quickly. Look at 3k changes. Doesnt look like anything is going to help with rod bearing issue anyway. However, you might try a left field approach using a oil additive like Lubegard and/or high friction modified oils with moly etc.
I would like to see those shoot rod bearings in S55. I mean, it would help a lot to other owners. Statements like: well, BMW had issues, etc. will not help anyone.
 
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26,361
Location
PNW
I'm really surprised BMW engineers haven't made the proper changes to the bearing design, and/or oiling system to make the bearings last longer. Seems like there is an ongoing issue with the engines that eat bearings way too early in life.
 
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11,663
Location
Colorado Springs
I'm really surprised BMW engineers haven't made the proper changes to the bearing design, and/or oiling system to make the bearings last longer. Seems like there is an ongoing issue with the engines that eat bearings way too early in life.
We did not see ANY evidence of that. This is assumption by OP based on previous M engines and the fact that engine is tuned.
Some issues might pop out with engines that are tuned to ridiculous levels since that is possible with turbo engines.
S55 is developed from N55 that was not tuner friendly. BMW could not extract 420hp safely out of N55, so they changed block etc. But, I would not bet on S55 that it can take some ridiculous levels of power. But, that is not BMW's issue. So far there is zero evidence of rod bearing failures on S55 without tune.
New M engine will be able to take a lot of aftermarket changes.
 
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64
Location
Norway
Can knock and superknock in DI engines damage bearings? I think i read about that quite often, caused by old spark plugs and bad coils and crappy walmart gasoline in tuned cars
 
S55 aren't known for bearing wear like the S65, S85, S54 motors were. Please don't use the same set of criteria for a completely different engine. Not only that, but this motor was based on the N55 and uses LL01 oil. 0w40 is TOTALLY fine for this car, the important thing is that it meets spec, that's all that matters. I have owned my S55 since 2015 and have used nothing but LL01 oils (Castrol 0w40/0w30 / BMW 5w30 / Ravenol 0w40SSL).
 
Messages
116
Location
Ontario, Canada
The only M engines that I know of that have had bearing issues were the s65 and s85 and they are the same engine, one with 2 fewer cylinders. The S50 from your '98 M3 was never turbocharged so if there is issues with that engine it's on you.
I have NEVER heard of problems with s55.
I agree with edyvw on his posts. The engines with issues were high revving NA with really tight tolerances and thick oil. Drivers probably didnt wait for proper oil temps prior to revving it out.
Also the current S58 is definitely over built, the block is identical to the diesel engine and has already been proven to handle LOTS of power.
 
Messages
1,119
Location
Vancouver
The only M engines that I know of that have had bearing issues were the s65 and s85 and they are the same engine, one with 2 fewer cylinders. The S50 from your '98 M3 was never turbocharged so if there is issues with that engine it's on you.
I have NEVER heard of problems with s55.
I agree with edyvw on his posts. The engines with issues were high revving NA with really tight tolerances and thick oil. Drivers probably didnt wait for proper oil temps prior to revving it out.
Also the current S58 is definitely over built, the block is identical to the diesel engine and has already been proven to handle LOTS of power.

The S54 in the E46 M3 had so many problems with the first few years they were actually recalled.
 
Messages
34,034
Location
Southern NJ
A family member just got a X3 M40i, which uses a 0w20. FWIW, I called the guys at bimmerworld out of curiosity because they highly recommend Red Line. The guy said to me that engines remain extremely clean and engines last longer with Red Line. He mentioned the rod bearing issue.


Here is a recent UOA of the 0w40 Turbo oil. 50%GTL and PAO.

 
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728
Location
EU
When both sides don't easily want to read and understand, activims won't make a winning team. Spare the 540 spam in this one, please.

What data is this recommendation of grade based on?
 
Messages
8,048
Location
Michigan
BMW high performance engines have had a near 20 year record of having rod bearing issues. In the pursuit of HP and minimizing internal friction, they have narrowed the bearing from the legacy rod bearing that didn't have any issues. There were also come clearance issues for a period form 2003-2013. This combined with the fact that the HP/cylinder continues to climb makes me nervous on my current engine, the S55 (M3/M4). The did increase the bearing width over the last two generations, but still isn't as wide as the older bearings. The factory oil recommended is a 0W-40, and I'm currently running the Castrol Edge 0W-40 A3/B4 oil.

I've seen a hand full of posts were rod bearings were already replaced at 30,000-60,000 miles with a lot higher wear that I would expect. I'm running this because during my initial research, this looked like it had a higher percent of group IV oil, where Mobil 1 0W-40 FS was group III. Not 100% sure since all of this is hard to pin down. My first oil analysis got lost, and I'm due for an oil change. I drive the car EXTREMELY hard, and eventually plan to modify it running E85 adding 150+ hp over the stock output.

I saw Mobil's 0W-50 racing oil and it has me thinking. Anyone on here run Mobil 0W-50 on a newer vehicle on the street? I'd like the higher film strength of the 50 weight, but that comes with extreme levels of zinc and phosphorus. Can Mobil 1's oil has generally said it is safe to run and blend with other oils. Thoughts on substituting a quart or two of the 0W-50 in the next oil change if I switch to Mobil 1 0W-40 FS? Any other oils I need to be considering? I run 15W-50 in my older turbo BMW, but concerned with the large difference in the 0W vs 15W, but would like the little extra zinc and phosphorus that it comes with.

Let me know your thoughts, thanks.
In Texas? Forget the wide viscosity spreads. Redline 15w50.
 
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