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First oil change since DIY鈥檌ng my rod bearings at 82k miles (87k on her now). Looks like the ACL bearings are holding up fine and the DIY was successful 馃憤. Time to increase the shift revs and let her sing again 馃槂馃槂馃槂.
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Discussion Starter #4
Congrats on the report but you've been babying the car for 5k miles?! You must of been going insane... lol
Lol, yep...only shifting at or below 4,500 rpm...no M mode for the first 1000 miles of it either just to be safe 馃槱. I wouldn鈥檛 have been so cautious, but it was like a 4 day job doing it my self so wanted to be sure everything was right before getting on it again, lol. I did learn a lot and made a nice DIY video series for my YouTube channel, but not ready to do that job again any time soon for sure.
 

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Rod bearings don't really need breaking in...
Yep...I agree. I wasn鈥檛 being easy for break in, I was mainly concerned that I did everything right since I did them myself and had to get enough miles on it to get an decently accurate oil analysis. If something was wrong, I鈥檇 rather catch it in the oil analysis than have spun a Bearing, lol.
 

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Discussion Starter #6
Congrats on the report but you've been babying the car for 5k miles?! You must of been going insane... lol
馃ぃ馃ぃ馃ぃ. I just realized that my iPad logged me in as my original member name that I never Even made a post with...that鈥檚 crazy, lol. This is Waitingondapig
 

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Lol, yep...only shifting at or below 4,500 rpm...no M mode for the first 1000 miles of it either just to be safe 馃槱. I wouldn鈥檛 have been so cautious, but it was like a 4 day job doing it my self so wanted to be sure everything was right before getting on it again, lol. I did learn a lot and made a nice DIY video series for my YouTube channel, but not ready to do that job again any time soon for sure.
What type of oil 10W-60 ?
 

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That oil is too thick on start up, causing the original rod bearing issues.
Failures
.
The BMW M3/M5 models have had an ongoing problem with rod bearing failures for a number of years now. The M3鈥檚 S65 V-8 engine was derived from the M5鈥檚 S85 V-10 engine. They share the same basic architecture and aluminum construction.
.
See Tech Article 29 540RAT blog
 

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That oil is too thick on start up, causing the original rod bearing issues.
Failures
.
The BMW M3/M5 models have had an ongoing problem with rod bearing failures for a number of years now. The M3鈥檚 S65 V-8 engine was derived from the M5鈥檚 S85 V-10 engine. They share the same basic architecture and aluminum construction.
.
See Tech Article 29 540RAT blog
It鈥檚 not just the oil, jcolley observed bad wear on 14k old rod bearings using nothing but 0w-40. That鈥檚 way over simplifying the issue. I鈥檓 not sure any one person has the consensus. I鈥檓 most compelled by the clearance being too tight stock regardless of oil, which is why many including myself replace the bearings with ones that have opened the clearance up a bit. Maybe 10-60 has a part to play in it all, but definitely not the end all be all
 

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540 RAT CONCLUSION
.
"Short of rebuilding those engines correctly with proper clearances, which is what is actually needed, the one thing owners can easily do to significantly help with this rod bearing problem, is to run a much thinner oil than the insanely thick 10W60 that BMW had specified for years. I recommend selecting a highly ranked 5W30 API SN oil from my Wear Protection Ranking List, which will make a HUGE improvement in rod bearing oil flow/lubrication/cooling, compared to the more commonly used super thick 10W60. This one significant change may well prevent having to rebuild those engines, and would go a long way toward eliminating rod bearing failures in many M3/M5鈥檚". Also if you read the testing results not all oils provide the wear resistance with similar viscosities.

Also, Someone emailed him with some practical experience.
Hi Rat,
.
Some time ago I wrote here that I changed the oil viscosity in my BMW S54-6-cylinder-M-engine from the suggested 10W60 to 0W40 using Mobil1 New Life.
.
Now I have covered some 50,0000 kms since then (before it was 5 W 50 for two oil changes, equaling approx. another 15.000 kms). Engine has reached 92,000 and I decided to have the rod bearings replaced.
.
Some owners make frightening experiences on this occasion: Wear patterns far from normal, rubbed-through layers with shiny copper exposed.
.
Guess what?
.
鈥淣othing to worry about here. Still enough life in the first layer of the bearing for another (!!) 90,000 kms. Wear pattern isn鈥檛 very unusual for this engine: Even and over the whole surface of the bearings each of them alike, no spotting visible.鈥
.
Rooted back to two aspects: Quickest possible build-up of oil flow after cold start due to 鈥0W鈥 and best possible 鈥渙il cushion鈥 in the bearing due to high flow with reduced temperature throughout the whole bearing.
.
There were worries about the enormously high pressure in the VANOS-system were that the oil would shear down too quickly and thus failure of the VANOS would be the result. In addition much higher wear on the valve train would be the inevitable result.
.
How wrong can that worry be?
.
No visible wear on camshafts and valve train, VANOS working perfectly and very quiet even after cold start up. Valve clearances have to be adjusted for the first time in more than 90,000 kms.
.
So 鈥 lesson learnt from practical experience:
.
Oil flow and protection by a good quality engine oil are much more important than 鈥渟teady oil pressure鈥 at the highest possible numbers.
.
As for using the suggested super thick 10W60 鈥 Myth busted! It is not needed.
.
Best wishes
Markus
.
 

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My advice: run whatever oil you feel is appropriate for how and where you drive your car. Pull the bearings and get your answer.

You can run 10w60. Ask me how I know. The thread below is based on my s85 on OEM clearance bearings and 10w60 motorcycle oil. Subsequently, I'm still on 10w60 and the enlarged BE bearings today.

Running total of my bearing life:

1. OEM (leaded) 0 to 80,0000 miles.
2. OEM (leaded) 80,000 to 150,000 miles.
3. BE 150,000 to present, which is 171,000+ miles.

My OEM bearings looked good after 60,000 miles, running 10w60. I will pull my BE bearings for giggles in 40,000 miles to see how they compare to my OEM bearings.

This is what broken-in OEM rod bearings look like after 60,000 miles of hard driving, but never put away wet. I thought I鈥檇 start a separate thread on my latest rod bearing journey. You can run 10w60 motorcycle oil, if you know how to drive this engine.



This is also a big middle finger to all the FU-Tube s85 鈥淭op Five Things I Hate鈥 experts. These cars are only as good as the previous owner commitment (financial) to the health of this platform. Think about this parallel with your own health. What would happen if you didn鈥檛 go to the dentist in 5 years, or 10 years? Your mouth would be all jacked up, if you only brushed and flossed. Some of these cars have never been to the dentist for a deep cleaning, outside of the laughable free scheduled maintenance, which probably ended three to five years ago.

It always cracks me up, when I read a classified that states their car was 鈥渞esponsibly driven鈥 and then the seller adds 鈥渘ever tracked!鈥 These cars can be responsibly driven AND tracked.

This time around, I had OMS use BE bearings from FAMS. BE was not available at the time of my last replacement in 2013.

For me, it was either OEM-L (leaded) or BE. The OEM-L is traceable and well documented, while the updated 702/703 are not able to be traced with a BS report.

Running total of my bearing life:

1. OEM (leaded) 0 to 80,0000 miles.
2. OEM (leaded) 80,000 to 150,000 miles.
3. BE 150,000 to present.

I鈥檝e driven about 120/130 of the 150,000 miles. My clutch was replaced by the previous owner at about 18,000 miles before I bought the car. My throttle actuators are original too. I have never seen my after-thought 6MT transmission overheat at the track 鈥 which was all the talk in the early years.

I also replaced both electric oil pumps, and all my VANOS related items, which lasted for 150,000 miles.

Originally, I replaced my first set at 80,000ish. They were trashed. Thread can be found here:
Rod bearings at 84,000 miles

My last BS report before this replacement:
137,000 mile update on rod bearings replaced 53,000...

Since my last replacement in 2013, I continued to follow my 鈥渘ormal鈥 start-up and driving procedures 鈥 track days included. 3000 mile-ish oil interval on 10w60 Motul motorcycle oil.

I鈥檓 looking forward to another 60,000 miles.


Sent from my iPhone using Tapatalk
My full thread here:
 
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540 RAT CONCLUSION
.
"Short of rebuilding those engines correctly with proper clearances, which is what is actually needed, the one thing owners can easily do to significantly help with this rod bearing problem, is to run a much thinner oil than the insanely thick 10W60 that BMW had specified for years. I recommend selecting a highly ranked 5W30 API SN oil from my Wear Protection Ranking List, which will make a HUGE improvement in rod bearing oil flow/lubrication/cooling, compared to the more commonly used super thick 10W60. This one significant change may well prevent having to rebuild those engines, and would go a long way toward eliminating rod bearing failures in many M3/M5鈥檚". Also if you read the testing results not all oils provide the wear resistance with similar viscosities.

Also, Someone emailed him with some practical experience.
Hi Rat,
.
Some time ago I wrote here that I changed the oil viscosity in my BMW S54-6-cylinder-M-engine from the suggested 10W60 to 0W40 using Mobil1 New Life.
.
Now I have covered some 50,0000 kms since then (before it was 5 W 50 for two oil changes, equaling approx. another 15.000 kms). Engine has reached 92,000 and I decided to have the rod bearings replaced.
.
Some owners make frightening experiences on this occasion: Wear patterns far from normal, rubbed-through layers with shiny copper exposed.
.
Guess what?
.
鈥淣othing to worry about here. Still enough life in the first layer of the bearing for another (!!) 90,000 kms. Wear pattern isn鈥檛 very unusual for this engine: Even and over the whole surface of the bearings each of them alike, no spotting visible.鈥
.
Rooted back to two aspects: Quickest possible build-up of oil flow after cold start due to 鈥0W鈥 and best possible 鈥渙il cushion鈥 in the bearing due to high flow with reduced temperature throughout the whole bearing.
.
There were worries about the enormously high pressure in the VANOS-system were that the oil would shear down too quickly and thus failure of the VANOS would be the result. In addition much higher wear on the valve train would be the inevitable result.
.
How wrong can that worry be?
.
No visible wear on camshafts and valve train, VANOS working perfectly and very quiet even after cold start up. Valve clearances have to be adjusted for the first time in more than 90,000 kms.
.
So 鈥 lesson learnt from practical experience:
.
Oil flow and protection by a good quality engine oil are much more important than 鈥渟teady oil pressure鈥 at the highest possible numbers.
.
As for using the suggested super thick 10W60 鈥 Myth busted! It is not needed.
.
Best wishes
Markus
.
Lighter oil alone will not magically fix the rod bearing wear problems. Telling people it will is disingenuous. At extremely cold temperatures (near or below 0 F) a lighter oil is probably a good idea for cold starts. Since you posted extremely vague anecdotal evidence from an unproven source, I invite you to poke around this forum and see for yourself the oil threads with first hand experience. You can run whatever weight oil you want, but make sure you鈥檙e telling others accurate info. Running lighter oil is not an excuse for not replacing rod bearings.
 

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No one said lighter oil will fix the rod wear bearing problem only that it would help reduce wear. Read the blog. Why anecdotal and unproven? 10W 60 oil is way too thick. Think about it your trying to pump mollases versus corn syrup
 

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My advice: run whatever oil you feel is appropriate for how and where you drive your car. Pull the bearings and get your answer.

You can run 10w60. Ask me how I know. The thread below is based on my s85 on OEM clearance bearings and 10w60 motorcycle oil. Subsequently, I'm still on 10w60 and the enlarged BE bearings today.

Running total of my bearing life:

1. OEM (leaded) 0 to 80,0000 miles.
2. OEM (leaded) 80,000 to 150,000 miles.
3. BE 150,000 to present, which is 171,000+ miles.

My OEM bearings looked good after 60,000 miles, running 10w60. I will pull my BE bearings for giggles in 40,000 miles to see how they compare to my OEM bearings.



My full thread here:
This was great timing. I was just about to ask you about your bearings when changed. Mine were done by the PO at 99k and I'm coming up on 120k. Like you my car gets a proper warm up, highway miles and of course days at the track. I am testing at each oil change(3k) and I'm committed to the platform. I wish I had a 6MT but I can always do that later. I have maybe 30-40k to go but rod bearings were in the plan before I bought the car.

I must say that the location of wear looks odd to me. I am used to seeing it more in the center of the bearing. Your second set looks like they could have gone a lot more miles.
 
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