The E92 BMW M3 is an incredible car. It looks great, handles fantastically and, most importantly, has one of the all time great performance engines. The 4.0 liter naturally-aspirated V8 in the E92 M3 (codenamed S65) and is a masterpiece. Not only does it make 414 hp but it does so by revving past 8,500 rpm and makes the most glorious noise. It’s also the only V8 ever fitted to an M3, so it’s quite special. However, the S65 engine does have one fatal flaw — rod bearings.
So what are rod bearings? Basically, their little metal bearings that sit between the crankshaft and the base of the connecting rod. They’re usually made from a softer metal than both, in this case copper. In the case of the S65 engine (and S85 V10 in the E60 M5) They fail because of very tight tolerances between the rod bearings and the crankshaft. So when the engine oil is cold, thus quite viscous, it can’t lubricate them well enough to handle the high revs that the engine is capable of. So if you start the car up and not warm the car up before using high revs, you can prematurely wear the rod bearings down. Now, if the rod bearing wears down enough, it can spin (You might have heard of having a spun bearing before) This is very, very bad and can lead to and engine being completely lunched, require either an entire replacement or a complete rebuild.
Now there is a lot of internet scaremongering, that all bearings will go bad at some point and destroy your work of art engine, but that's not the case, a well looked after S65, that has been maintained correctly and warmed up properly before going hell for leather, should not be a problem, and if further looked after, can go on without issue (its not fool proof but pretty safe) however those that have S65's with a few owners and miles, well you don't know how its been looked after or treated. You can pay for an oil analysis to be done, that can give you an unseen indication of your S65 bearing wear, but it can like me, just boil down to peace of mind weather you have it done or not.
I have had a few M3 V8's but I have always had a BMW approved used car warranty, so my approach was always "if she blows" ill get a new S65. That's now not the case and as the cars get older and with more miles, its hard to get one with a BMW warranty and after 60k miles that BMW warranty cost doubles and in most cases over £2k a year! So onto my current E92 M3, it has 62k miles and several owners. It has always been on my mind about having them done, and I can say that I did not want to drive the car properly until I did, so it sat on the drive waiting for the 7 week wait to have them done. I have now handed over £1500 and the work is done with upgraded bolts and bearings. Running in is a bit of a pain and is 500 miles and an oil change after 1000 miles.
This thread is for posting up your thoughts and experiences and show us your bearings with year and mileage after the change.
Here is mine 2011, 62k miles. and no wear or signs of contact at all! Like I said they did not need to be done, and I may very well have just wasted the money, but here's the thing, It was always in the back of my mind that they might be worn, so I was always going to have it done, and I feel better now they have!
Hope this thread helps and provokes some healthy discussion and reviews on a hot topic for V8 M3 owners and buyers.
So what are rod bearings? Basically, their little metal bearings that sit between the crankshaft and the base of the connecting rod. They’re usually made from a softer metal than both, in this case copper. In the case of the S65 engine (and S85 V10 in the E60 M5) They fail because of very tight tolerances between the rod bearings and the crankshaft. So when the engine oil is cold, thus quite viscous, it can’t lubricate them well enough to handle the high revs that the engine is capable of. So if you start the car up and not warm the car up before using high revs, you can prematurely wear the rod bearings down. Now, if the rod bearing wears down enough, it can spin (You might have heard of having a spun bearing before) This is very, very bad and can lead to and engine being completely lunched, require either an entire replacement or a complete rebuild.
Now there is a lot of internet scaremongering, that all bearings will go bad at some point and destroy your work of art engine, but that's not the case, a well looked after S65, that has been maintained correctly and warmed up properly before going hell for leather, should not be a problem, and if further looked after, can go on without issue (its not fool proof but pretty safe) however those that have S65's with a few owners and miles, well you don't know how its been looked after or treated. You can pay for an oil analysis to be done, that can give you an unseen indication of your S65 bearing wear, but it can like me, just boil down to peace of mind weather you have it done or not.
I have had a few M3 V8's but I have always had a BMW approved used car warranty, so my approach was always "if she blows" ill get a new S65. That's now not the case and as the cars get older and with more miles, its hard to get one with a BMW warranty and after 60k miles that BMW warranty cost doubles and in most cases over £2k a year! So onto my current E92 M3, it has 62k miles and several owners. It has always been on my mind about having them done, and I can say that I did not want to drive the car properly until I did, so it sat on the drive waiting for the 7 week wait to have them done. I have now handed over £1500 and the work is done with upgraded bolts and bearings. Running in is a bit of a pain and is 500 miles and an oil change after 1000 miles.
This thread is for posting up your thoughts and experiences and show us your bearings with year and mileage after the change.
Here is mine 2011, 62k miles. and no wear or signs of contact at all! Like I said they did not need to be done, and I may very well have just wasted the money, but here's the thing, It was always in the back of my mind that they might be worn, so I was always going to have it done, and I feel better now they have!
Hope this thread helps and provokes some healthy discussion and reviews on a hot topic for V8 M3 owners and buyers.
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