Rod Bearings Replaced

[Mikulski]

Hey everyone I recently got my rod bearings replaced almost 2 weeks ago and I would like to share my results. Car Specs:

July 2009 build date
Purchased at 54,522 miles
Bearings replaced at 58,768 miles
Three previous owners

I had no abnormal noises other than the metallic "tink" when the clutch engages (Guibo) which will be replaced soon. Car ran great with VERY little exterior and interior imperfections. I was aware of rod bearings BEFORE I purchased the car but I had the impression that it was strictly with the S85 engine. When I started reading of the rod bearing failures on the forum for the S65 I had the urge to get them replaced ASAP. It was actually quite hard for me to enjoy the car not knowing what damage was under the hood. If I bought it from the original owner I would have greater peace of mind but this wasn't the case. Better safe than sorry for a relatively inexpensive procedure.

I'm grateful I went through with this as I was told this was the beginning of the end for the bearings. No damage was done to the crankshaft In order to REDUCE unnecessary damage proper warm up and ~5K mile oil changes will be adhered to. I want to say this is merely to help everyone get a better idea of if they should have theirs replaced as well. In no way do I mean to frighten anyone that their rod bearings are going to fail.


Pictures:
















Cylinder #1 Rod Bearing (Upper)



Cylinder #2 Rod Bearing (Upper)



Cylinder #3 Rod Bearing (Upper)



Cylinder #4 Rod Bearing (Upper)



Cylinder #5 Rod Bearing (Upper)



Cylinder #6 Rod Bearing (Upper)



Cylinder #7 Rod Bearing (Upper)



Cylinder #8 Rod Bearing (Upper)

[tinman831]

=/

[Race_Doc11]

How much does it cost to replace them?

[aus]

Thanks. Good post.

[Rupes]

Yours look better than most I've seen. Did you do any oil analysis prior to this?

[Wendall]

Mine looked exactly the same at 51k miles. I'm very happy I had them replaced. Peace of mind.

[tdott]

Nice. Thanks for sharing. Where did you get them done and what did you replace them with?

[dparm]

Mikulski,

I would still recommend you get UOAs done to determine the correct oil change interval and to establish baseline/monitor trends in the long-term.

[Mikulski]

Originally Posted by dparm

Mikulski,

I would still recommend you get UOAs done to determine the correct oil change interval and to establish baseline/monitor trends in the long-term.

I agree dparm. I will be starting a journal for my car.

Originally Posted by tdott

Nice. Thanks for sharing. Where did you get them done and what did you replace them with?

Got it done by ACM in Fairless Hills NJ. They used BMW's upgraded bearings.

Originally Posted by Rupes

Yours look better than most I've seen. Did you do any oil analysis prior to this?

Thought about doing an analysis of my oil when I got the bearings replaced. Slipt my mind to grab a sample though.

[PhillyNate]

I do believe this rod bearing issue is WAY overblown but those pics DO NOT make me wish I had the car back...Thanks for posting. Only 54k miles, yikes.

[marksae]

Thanks for posting your findings. It's good info.

While your rod bearings don't look great, they don't look as bad as some of the other pictures posted on this forum.

I didn't know BMW offered "upgraded" bearings. Are your bearings treated?

[kerrit]

Thanks for posting. Agreed that these bearings don't look as bad as most posted - they aren't even really into the copper layer. I think this still proves though that this should definitely be a maintenance item - probably around 75k miles for me, assuming blackstone reports look decent.

[thetastelingers]

I would like to know cost as well.
Do they just R&R or do they mic the crank while they are in there?
Do they install the bearings on the rod and mic them as well?

Thanks for sharing.

[Killerfish2012]

I agree with others that the bearings don't look that bad. I would say they look like the previous owners ran 10W60, for 15K intervals. Once bearing failure is imminent, it should sound like this:

If your motor didn't sound anything like that, then those bearings could have gone 50-100K miles or more. for all we know the new bearings may go back to looking like the old ones within 15K miles, so long as you still use 10W60

[Mikulski]

Originally Posted by Killerfish2012

I agree with others that the bearings don't look that bad. I would say they look like the previous owners ran 10W60, for 15K intervals. Once bearing failure is imminent, it should sound like this:

If your motor didn't sound anything like that, then those bearings could have gone 50-100K miles or more. for all we know the new bearings may go back to looking like the old ones within 15K miles, so long as you still use 10W60

Thanks for the input Killerfish. I agree the bearings may have gone that much longer but why would I wait and let it get to the point of imminent failure? At that point you can be damaging your crankshaft, but hell if you're gonna sell your car before it gets to that point and would rather have someone else deal with that headache go ahead. Having said that I really hope the "upgraded" bearings as they called are better for the car.

[Killerfish2012]

Originally Posted by Mikulski

Thanks for the input Killerfish. I agree the bearings may have gone that much longer but why would I wait and let it get to the point of imminent failure? At that point you can be damaging your crankshaft, but hell if you're gonna sell your car before it gets to that point and would rather have someone else deal with that headache go ahead. Having said that I really hope the "upgraded" bearings as they called are better for the car.

You're welcome bud. I just got my '09 M3 not too long ago, and I'm at 98K miles now. The engine sounds prestine, so I'm not worried about this rod bearing thing. I'm not going to change a part if nothing is wrong with it. Looks like the previous owner used Mobil 1 10W40 high mileage, so it's obvious that using a very thick oil like castrol 10W60, and running oil 15K mile oil changes is pretty much asking for it.

[Mikulski]

Just got back my Oil analysis. Remember this was a "Break in " period in which I didn't exceed 4K rpm for the first ~1800 miles.....EVER

[Gossypiboma]

You don't have to break in new bearings so as long as that is all you replaced then there was no reason to put around under 4K rpm.

[Mikulski]

Originally Posted by BigBoosting

You don't have to break in new bearings so as long as that is all you replaced then there was no reason to put around under 4K rpm.

I'm assuming this was to ensure proper fitment as there may have been slight imperfections on the bearings during manufacturing. By adhering to lower RPMs the crankshaft will have a greater opportunity to remove these imperfections gradually.

[JsL]

Originally Posted by Killerfish2012

You're welcome bud. I just got my '09 M3 not too long ago, and I'm at 98K miles now. The engine sounds prestine, so I'm not worried about this rod bearing thing. I'm not going to change a part if nothing is wrong with it. Looks like the previous owner used Mobil 1 10W40 high mileage, so it's obvious that using a very thick oil like castrol 10W60, and running oil 15K mile oil changes is pretty much asking for it.

You make it sound like 10W60 and BMW's oil change interval is the definitive cause of bearing failure. That just adds to the paranoia around here.

I think the correct statement is to get an oil report and determine 1) if you have bad bearings 2) what is the correct oil chamge interval for your particular engine 3) ability to monitor your bearing wear

[MFKN3]

Originally Posted by JsL

determine 1) if you have bad bearings

If it's an S65, that's a given.

Well it's not actually the bearings, but the tolerance and the oil being too thick at startup which then results in bearing damage.

[SenorFunkyPants]

Its worth noting that if this bearing set was sent to Clevite for analysis they would categorize the wear as perfectly normal.
Given the predominant wear pattern seen in poor condition bearings removed from S65 engines - one or two upper bearings showing copper - I suspect that the problem is nothing at all to do with the 10W60 oil but instead a function of either poor quality control of the bearings shells themselves...where some are out of thickness spec promoting high wear in those bearings while others remain perfectly normal....or some other mechanism that causes high wear in only one or two bearings.
Its highly unlikely that using 10W60 can cause selectively high wear in only a couple of bearing sets.