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I have taken oil samples throughout the life of my stock-engined 2007 RS - currently with 40k miles. I have always used Mobil1 or Castrol Syntec, changed at 3000 miles. Sending these samples to Blackstone, I have been comforted by their summary at the top of the page stating everything looked really fine. I have numbers in the 0-2 range (ppm) for lead and tin, aluminum 5, and iron 10, but my copper is measuring 18. A friend stated that his M3 with 100K miles only measures 5ppm for copper, and a friend of his had another M3 with 38ppm lead, and 38ppm copper. Upon the subsequent teardown, it was discovered that the rod bearings were severely worn. The elevated copper readings were explained as: Copper is a plain bearing plating that isn't exposed until the layers next to the crank journal (the lead and tin) are worn through. My question is whether 18ppm copper seems of concern to anyone who has regularly had oil samples analyzed? Are there other sources of copper wear that would show up in an oil analysis? Thank you in advance.
Last edited by HarmonyJim; 10-04-2021 at 01:22 PM.
Have you seeing any flakes or shavings in the oil or filter? I have heard that the GT3 engines are known to shed more debris than others. I'm not sure how true that is.
Last edited by Robocop305; 10-04-2021 at 12:36 PM.
I'm not sure if it eases your concerns, but M3 consume rod bearings as a known wear item. It's very common for M3s to have a rod bearing problem or lose the engine if they're neglected. To my knowledge there aren't known issues for rod bearings on any Mezger case / dry sump porsche engines. I've split cases that had a lot of copper showing on the oil pump / intermediate shaft plain bearings, but never heard of a Mezger engine failing from IMS problems (very different mechanical design than the water cooled cars that have big issues).
Has that reading been consistent over time or is it increasing?
I looked up my very first analysis, and it showed 14ppm for copper at approx 12,000 miles, and has measured as low as 8ppm at 15,200 miles. It has stayed within an 8ppm to 18ppm range since I first purchased the car at 9,000 miles in 2012.
I'm not sure if it eases your concerns, but M3 consume rod bearings as a known wear item. It's very common for M3s to have a rod bearing problem or lose the engine if they're neglected. To my knowledge there aren't known issues for rod bearings on any Mezger case / dry sump porsche engines. I've split cases that had a lot of copper showing on the oil pump / intermediate shaft plain bearings, but never heard of a Mezger engine failing from IMS problems (very different mechanical design than the water cooled cars that have big issues).
Yes, I have heard this is a known issue with M3s. My friend's mechanic is insisting he replace the rod bearings in his M3 even though the measurements he is seeing are far less than the numbers seen in my RS. Could be a case of his mechanic just wanting more work for himself.
Yes, I have heard this is a known issue with M3s. My friend's mechanic is insisting he replace the rod bearings in his M3 even though the measurements he is seeing are far less than the numbers seen in my RS. Could be a case of his mechanic just wanting more work for himself.
I think it's fairly widely accepted that M3s will get rod bearings on a mileage interval, and do the oil checks to make sure there isn't something happening between the upkeep. The mechanic could be looking to line his pockets, but he might also just be trying to make sure your friend gets good life out of the bottom end of his engine.
Have you seeing any flakes or shavings in the oil or filter? I have heard that the GT3 engines are known to shed more debris than others. I'm not sure how true that is.
No, I have never seen any shavings or filings, and I do look over my filter at each oil change.
Yesterday I went to the source and called Blackstone. According to the tech at Blackstone, the numbers are fine. He said there are many sources of copper other than the plain bearings (he mentioned bronze bushings as a potential source). He also mentioned that the lead levels would need to be very high if the rod/main bearings were wearing, and lead was measured at 0-2ppm, so that is definitely not an issue. He also agreed with Auto_Werks 3.6 that M3s are known as rod bearing destroyers. Considering GlenGT3 is measuring numbers much higher than mine, and he states the engine shows no signs of any internal distress, I guess I am just fine. Oh well, I guess I'll have to come up with another line of argument to convince myself (and my wife) to put a 3.9 SW in the back!!
Last edited by HarmonyJim; 10-05-2021 at 12:41 PM.
Just to add as another data point, attached is the history of my 2010 since new. I'm waiting for another sample to come in from the most recent oil change.
By request, adding recent oil analysis with low mileage longer interval (2 year).
Great report! You're running M1 0W40? For 2k miles, glad to see it stayed within spec as I know many have reports where it shears down quickly. Also, it's great to see that a longer interval (2 years) does not really have any issue.
Thank you for posting the update. Can you clarify the intervals? The most recent sample date is 9/2021 and the prior sample shows 11/2013, indicating an 8 year, 2311 mile interval. Were there more recent samples which are not shown on this report? Trying to reconcile the 672 mile interval shown on report and 2 year interval you mentioned.