2012 M3 rod bearings

[asherul]

I read that at 2011 BMW changed the material of the bearings. Don't know if it's reliable info.
As a new owner of 12/2012 M3 , would you still recommend replacing the bearings?
The car did 81000 m.

Thanks.

[br2wdc]

Short answer is YES.

The main issue is while the risk is low, it's a catastrophic failure of the engine if you spin a bearing, which will cost you $20k USD to replace the engine.

So spending $3k to insure it doesn't happen makes sense for many of us, if not the majority of E9x M3 forum members.

Originally Posted by asherul

I read that at 2011 BMW changed the material of the bearings. Don't know if it's reliable info.
As a new owner of 12/2012 M3 , would you still recommend replacing the bearings?
The car did 81000 m.

Thanks.

[InnerBlueSkies]

Originally Posted by asherul

I read that at 2011 BMW changed the material of the bearings. Don't know if it's reliable info.
As a new owner of 12/2012 M3 , would you still recommend replacing the bearings?
The car did 81000 m.

Thanks.

They changed the material but it didn't fix the problem. The newer bearing material reduces the benefits of oil analysis (no longer use lead).

[Cyberdemon]

It's a beaten to death topic you can spend hours reading about, but the philosophy on bearings is the same as one on extended warranties. It's entirely about a cost/risk proposition.

There is a statistically low chance your bearings will blow up your engine. But there is a chance, and that is astronomically expensive.

Changing the bearings will give you that piece of mind while simultaneously paying some dividend on resale because the next person who buys your car will likely have that be the first 3 words out of their mouth. "Rod bearings done?".

Is it urgent that you do it the second you pull the car in your driveway? No. But it's worth planning on budgeting for it and doing it when you have the time, unless you expect to be like some owners who flip the car after 5,000 miles.

[Mr. BMW]

Changing the bearings will give you that piece of mind unless the shop that does the work does something wrong and your engine blows up anyway....

[decimation1]

Originally Posted by Mr. BMW

Changing the bearings will give you that piece of mind unless the shop that does the work does something wrong and your engine blows up anyway....

ROFLMAO!!!

[nrubenstein]

Originally Posted by Mr. BMW

Changing the bearings will give you that piece of mind unless the shop that does the work does something wrong and your engine blows up anyway....

Or a main bearing fails.

[gds52]

Just sharing my thoughts as per my S54....
I got first oil analysis on my car when I bought it at 9k miles, lead n other readings were a bit higher than average. Then I tracked it moderately. after 2 track days between oil changes, next report showed lower readings. And subsequent analysis with 1-2 track days kept numbers low.
Bottom line is these engines are meant to be driven at higher oil temperatures, use those high revs (of course after its at operating temp) Babying these engines is not the best way. I was guided by my BMW Indy shop owner who owns many BMWs and is a BMW race car driver.

[asherul]

Thank you for all the replies.
Guess I'm ordering those BE bearings..

[CamasM3e93]

Originally Posted by asherul

Thank you for all the replies.
Guess I'm ordering those BE bearings..

I've owned a 2012 for about 6 months and have asked myself the same question. Somewhere on this forum there is a bar chart of known bearing failures by model year. The number of failures for 2012 and 2013 models with the harder material are fairly low relative to the other model years. Now, of course newer models have had less time to fail and there may be fewer M3s made in those two years - so raw numbers only tell you so much. But now we're talking 7-8 years on those models so that's a fairly reasonable time for it to start showing up and at the very least it appears the new bearing wears longer than the original bearing.

I have just 50k miles on mine and for now have no plans to drop in a sweet sweet supercharger. I've decided to defer the bearing job indefinitely. This is based on everything I've described, but also plenty of stories on this forum and others of people having replacement bearings fail unexpectedly, new issues caused by mechanics who don't change rod bearings all that often, etc. It also helps that I'm in a place economically where I could walk away from the car (painfully with tears) if it blew up. That's not a brag but what you would personally do if it did blow up is a good thing to throw into your $3k equation.

The job can be done by reasonably skilled home mechanics, better if on a lift, with lots of planning via many available video and print resources here and elsewhere. But one of those I've seen the guy came back months later to report he'd seated the bearing incorrectly leading to failure - he seemed fairly crafty and craftier than me so that swayed me to use a shop. Calls to one BMW dealer and two BMW local mechanics found nobody willing to take the job on. I did find the local rod bearing capable shop in PDX eventually, but know that this isn't a job you want to hire just anyone for.

[smyles]

Originally Posted by asherul

Thank you for all the replies.
Guess I'm ordering those BE bearings..

The RB cult welcomes thee.

[akkando]

Originally Posted by CamasM3e93

I've owned a 2012 for about 6 months and have asked myself the same question. Somewhere on this forum there is a bar chart of known bearing failures by model year. The number of failures for 2012 and 2013 models with the harder material are fairly low relative to the other model years.

2011 model year should have the updated bearings made with the new material. I think model year 2011 has had a bunch of failures but I'm going off memory of the chart. Certainly healthy to have a plan if the worst should happen and you lose a motor so life can go on.

[Scharbag]

Originally Posted by akkando

2011 model year should have the updated bearings made with the new material. I think model year 2011 has had a bunch of failures but I'm going off memory of the chart. Certainly healthy to have a plan if the worst should happen and you lose a motor so life can go on.

My 2011 MY M3 had 088/089 bearings, not the harder 702/703 bearings.

This is a statistics problem. There is no way to know if your bearings are too tight unless you look. At that point, it is very little effort to simply replace them with bearings that offer adequate clearance.

Cheers,