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    • This is what happens when you forget to replace your E9X M3 S65 V8 rod bearings - Blown S65 V8 pictures

      Rod bearing wear issues in the 4.0 liter S65 V8 in the E9X M3 are well known. Rod bearings also wear prematurely on the S85 V10 on which the S65 V8 is based but do to the superior oiling system of the V10 the problem is not exacerbated as it is on the V8.


      Things vary based on use as well. A car that is tracked or supercharged will see more wear than a stock car used for commuting. The bottom line however is that owners should replace their rod bearings before it is too late so that they can avoid what is pictured below.

      @Michael@GermanAutoWerks shared pictures of a blown S65 V8 from an E92 M3:

      Quote Originally Posted by German Auto Werks
      2011 m3 was brought to us for a engine noise. When we drained the oil metal was found in it. After pulling the oil pan we found as expected, spun rod bearings. Unfortunately the crankshaft had damage as well. Customer has decided to go the full rebuild route. Out the s65 comes! Have a few special pieces in mind for the new motor including a hardened crankshaft.
      Unfortunately, BMW has a history of mistakes with M3 engines dating back to the E46 M3 S54 and all the way up to the current F80 M3 S55. Someone should hold BMW accountable for knowingly selling motors with defects.












      This article was originally published in forum thread: When you forget to replace your rod bearings.. started by Michael@GermanAutoWerks View original post
      Comments 71 Comments
      1. Optigrab's Avatar
        Optigrab -
        So what is the culprit for the bearing wear? Bad bearings bad oiling bad engine design?
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by Optigrab Click here to enlarge
        So what is the culprit for the bearing wear? Bad bearings bad oiling bad engine design?
        I think it's a combination of bad factory bearing tolerances and the oiling system. They just went way too cheap like they pretty much do with everything now.
      1. Bowser330's Avatar
        Bowser330 -
        So if i was in the market for a used E92 M3, i would proactively swap out the bearings..

        But is it as simple as that? Are the upgraded bearings that much better than stock or will the same bearing wear issue come up again?
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by Bowser330 Click here to enlarge
        So if i was in the market for an E92 M3 i should proactively swap out the bearings? But is it as simple as that?
        It depends. What is the oil in the car? Are you in a cold or warm climate? How many miles on it? How was it used?
        Click here to enlarge Originally Posted by Bowser330 Click here to enlarge
        Are the upgraded bearings that much better than stock or will the same bearing wear issue come up again?
        It depends on whose bearings. I would assume VAC has the bearings down pat at this point along with the oil that should be used.

        If it was me, I'd swap the bearings and do an oil change for peace of mind.

        I've considered going dry sump to just not have any worries.
      1. Optigrab's Avatar
        Optigrab -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        It depends. What is the oil in the car? Are you in a cold or warm climate? How many miles on it? How was it used?


        It depends on whose bearings. I would assume VAC has the bearings down pat at this point along with the oil that should be used.

        If it was me, I'd swap the bearings and do an oil change for peace of mind.

        I've considered going dry sump to just not have any worries.
        Wonder if the bearings can be swapped with the engine in the car or the engine has to be pulled?
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by Optigrab Click here to enlarge
        Wonder if the bearings can be swapped with the engine in the car or the engine has to be pulled?
        Let's ask @Michael@GermanAutoWerks how he goes about it, which bearings he sources, and the complete cost.
      1. Optigrab's Avatar
        Optigrab -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        Let's ask @Michael@GermanAutoWerks how he goes about it, which bearings he sources, and the complete cost.
        Probably uses Frankenbearings
      1. lulz_m3's Avatar
        lulz_m3 -
        The "go to" bearings seem to be BE bearings, since they provide a little more tolerance. The oem bearings that came in 2011+ S65's also have slightly more clearance. The bearings can be changed with the engine still in the car, just need to drop the subframe.

        Also, the rod bearings arent the only issue. Plenty of other have had the main bearings let go, which obviously cannot be changed without pulling the motor.

        Its a really $#@!ty scenario, luckily i bought mine used with the bearings already done by VAC.
      1. Sticky's Avatar
        Sticky -
        What ever happened to that S65 engine defect lawsuit?
      1. lulz_m3's Avatar
        lulz_m3 -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        What ever happened to that S65 engine defect lawsuit?
        No idea. Statistically speaking, i think the issue is that not enough people have come forward. I forget the numbers, but the total number of reported failures vs produced S65's in the states is actually quite low. Hard to determine if there is a widespread issue for not. Its easy to let it cause paranoia.
      1. The Convert's Avatar
        The Convert -
        Yeah, I was about to ask how you would mitigate a bearing issue by just replacing the rod bearings. I would assume you would have the same issues with the main bearings as well.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by lulz_m3 Click here to enlarge
        No idea. Statistically speaking, i think the issue is that not enough people have come forward. I forget the numbers, but the total number of reported failures vs produced S65's in the states is actually quite low. Hard to determine if there is a widespread issue for not. Its easy to let it cause paranoia.
        It is an issue but it's more that someone can get hurt. I remember hearing about someone pushing their motor after they were told to replace the bearings and it let go. They were lucky not to hurt themselves or anyone else as they were going 100+ when it happened.
      1. Optigrab's Avatar
        Optigrab -
        Click here to enlarge Originally Posted by lulz_m3 Click here to enlarge
        The "go to" bearings seem to be BE bearings, since they provide a little more tolerance. The oem bearings that came in 2011+ S65's also have slightly more clearance. The bearings can be changed with the engine still in the car, just need to drop the subframe.

        Also, the rod bearings arent the only issue. Plenty of other have had the main bearings let go, which obviously cannot be changed without pulling the motor.

        Its a really $#@!ty scenario, luckily i bought mine used with the bearings already done by VAC.
        Are you talking about touchdown and the rod bearings being slightly out of spec on the large side?
      1. Michael@GermanAutoWerks's Avatar
        Michael@GermanAutoWerks -
        Click here to enlarge Originally Posted by Optigrab Click here to enlarge
        Probably uses Frankenbearings
        Hello,

        we use BE bearings. If you are just doing bearing the subframe is lowered and oil and is removed. Engine does not have to come out just for a bearing service.
      1. Optigrab's Avatar
        Optigrab -
        Click here to enlarge Originally Posted by Michael@GermanAutoWerks Click here to enlarge
        Hello,

        we use BE bearings. If you are just doing bearing the subframe is lowered and oil and is removed. Engine does not have to come out just for a bearing service.
        Thanks for the update.

        How many hours would a bearing replacment take?
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by Optigrab Click here to enlarge
        Thanks for the update.

        How many hours would a bearing replacment take?
        Yeah I'm curious on the labor as well.
      1. Steve B. CBR's Avatar
        Steve B. CBR -
        I believe there is a lot of this information in the ACL Bearing thread. Don't quote me, but I believe it was like 8 hours at $100 per hour and a total cost of $800 plus the cost of bearings, oil, and gaskets. They drop the subframe and come up through the oil pan, however this was only to replace the rod bearings, not the mains.
      1. Itsbrokeagain's Avatar
        Itsbrokeagain -
        I want that engine table Click here to enlargeClick here to enlarge
      1. Michael@GermanAutoWerks's Avatar
        Michael@GermanAutoWerks -
        Click here to enlarge Originally Posted by Steve B. CBR Click here to enlarge
        I believe there is a lot of this information in the ACL Bearing thread. Don't quote me, but I believe it was like 8 hours at $100 per hour and a total cost of $800 plus the cost of bearings, oil, and gaskets. They drop the subframe and come up through the oil pan, however this was only to replace the rod bearings, not the mains.
        8hrs is super low. Just for reference BMW Warranty time just to replace the oil pan gasket pays 5.9hrs. We charge 13.5hrs for rod bearing replacement on the s65.
      1. Michael@GermanAutoWerks's Avatar
        Michael@GermanAutoWerks -
        Attachment 52509

        Difference between a stock crankshaft and one that has had the hardening process done to it.