2011 E92 M3 160k mile, 55 track days, Rod Bearing changeout

[redpriest]

I'm the second owner. Car was a lease return auctioned off, picked up by used car dealer. Full maintenance history. 120k miles are mine, daily driven for 3 years. 180 mile round trip commuter car.

Car has no special baffled oil pan. Run everything up to slick tires on the track in this car. Detailed track history of my car is here, including all my PBS.

http://www.m3post.com/forums/showthread.php?t=1166259

Swapped out to BE Bearings and BE ARP bolts. Plastigauging clearances after install.

Bottoms are on the left of each pair.

I should add I warm the car up to 210 first before ripping up to 8600 RPM 5x a day at a minimum. I live in a rural area so at stop signs I will redline first and second gear.

BPM tune with red line limiter increased, pulley, intake, exhaust.

[shimmy23]

awesome! proof that rod bearings are a mystery with this car

[eternallx]

Wow seriously.... really good at 160k compare to others that posted

[E46M3forRay]

Those bearings are impeccable. I didn't expect to come out like that and have been waiting patiently how yours was going to turn out. Which oil were you using again?

Thanks for sharing!

[redpriest]

Originally Posted by E46M3forRay

Those bearings are impeccable. I didn't expect to come out like that and have been waiting patiently how yours was going to turn out. Which oil were you using again?

Thanks for sharing!

Been using Castrol TWS Motorsport 10w60 up to about 140k miles. My change interval up to 90k miles was 15k miles, then when I started tracking the car it would be 5000 miles, or 3-4 track days, whichever comes first.

I did use the BMW TwinPower branded 10w60 a couple times in the 90k-140k interval.

I'm using Ravenol 10w60 now since 140k miles.

Here are some of the oil analysis samples I did up to 100k miles (ignore the 9 quarts of make up oil added, I misunderstood what the field meant. My car only burns a quart of oil every 7k miles):

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[Helmsman]

Cheers Redpriest. Nice to see long mileage RBs coming out as they should. As these are OEM, what are the reasons to change to BE?

[redpriest]

Originally Posted by Helmsman

Cheers Redpriest. Nice to see long mileage RBs coming out as they should. As these are OEM, what are the reasons to change to BE?

I'm running with the assumption that I had a correct, magical tolerance stack of clearances from the factory.

To ensure I have the same clearance stack for the next 150k miles, I decided to go with the BE bearings as they are, by my understanding, hand binned the same way.

[Helmsman]

Originally Posted by redpriest

I'm running with the assumption that I had a correct, magical tolerance stack of clearances from the factory.

To ensure I have the same clearance stack for the next 150k miles, I decided to go with the BE bearings as they are, by my understanding, hand binned the same way.

Got it, thx.

[rcracin]

At 160k and more foreseeable track days, don't you think a motor refresh is in order? Main bearings, rings, and other gaskets and seals gotta be getting tired by now. Glad to see that the motor and car have held up well overall though. Outstanding reliability given your track use.

[///M Power-Belgium]

Originally Posted by redpriest

I'm running with the assumption that I had a correct, magical tolerance stack of clearances from the factory.

To ensure I have the same clearance stack for the next 150k miles, I decided to go with the BE bearings as they are, by my understanding, hand binned the same way.

Awesome !
A bearing replacement was not necessary in your situation , the condition of your bearings was still good to run another 150K miles ..

You run clearly with a winner from the German lottery !

[redpriest]

Originally Posted by rcracin

At 160k and more foreseeable track days, don't you think a motor refresh is in order? Main bearings, rings, and other gaskets and seals gotta be getting tired by now. Glad to see that the motor and car have held up well overall though. Outstanding reliability given your track use.

I did a compression test as well and it came back fine. I think the cost of main bearing replacement starts to approach used engine territory to the point where I don't think it's particularly worth it.

My engine has never been supercharged, which seems to be one of the leading causes of advanced main bearing wear/failure.

[L4ces]

Originally Posted by redpriest

I did a compression test as well and it came back fine. I think the cost of main bearing replacement starts to approach used engine territory to the point where I don't think it's particularly worth it.

My engine has never been supercharged, which seems to be one of the leading causes of advanced main bearing wear/failure.

Perhaps SCng stress and the change in driving habits increase wear for a bad set but mine were worn to copper and mine car is stock.

[dreamspeed]

good to see at least one rod bearing thread that turned out well

180 mile commute in the bay area?! Are you going from like Gilroy to SF? haha

Can't blame you though, housing prices in SF are friggin ridiculous.

[pbonsalb]

Originally Posted by L4ces

Perhaps SCng stress and the change in driving habits increase wear for a bad set but mine were worn to copper and mine car is stock.

OP has 2011 so no copper. I don't know what constitutes bad wear on the newer aluminum bearings.

[L4ces]

Originally Posted by pbonsalb

OP has 2011 so no copper. I don't know what constitutes bad wear on the newer aluminum bearings.

Aha! I missed that important detail.

[Denk]

I wouldn't kick those bearings out of bed!

[rcracin]

Originally Posted by redpriest

I did a compression test as well and it came back fine. I think the cost of main bearing replacement starts to approach used engine territory to the point where I don't think it's particularly worth it.

My engine has never been supercharged, which seems to be one of the leading causes of advanced main bearing wear/failure.

Compression test came back as in ok across all 8 cylinders? That motor has got to be tired. The compression is probably lower than that of a motor with much less miles. I suggest preventative maintenance before risking blowing it.

[redpriest]

Originally Posted by rcracin

Compression test came back as in ok across all 8 cylinders? That motor has got to be tired. The compression is probably lower than that of a motor with much less miles. I suggest preventative maintenance before risking blowing it.

Compression test results:

[statelax3]

Originally Posted by redpriest

Compression test results:

That ain't broke, don't fix it! Love seeing how well your M is doing.

[6ixSpd]

There is no reason to magically assume the motor is "tired" or needs a rebuild at 160k miles. Clearly it's running just fine, there is no reason to justify a tear down and rebuild just because of mileage number. If the car has lasted THIS long with that hard driven life, clearly its up to the task. If compression numbers were low/varying, OP had noticed a loss in performance, etc then maybe it would be time to look into a rebuild. Doing it just for the sake of mileage is dumb.

[tdott]

Originally Posted by E46M3forRay

Those bearings are impeccable.

I wouldn't say impeccable, there is still wear to the bearings which would be considered bad for a regular engine but less than average wear for an s65. He definitely got lucky with his motor.

With the rod bearing problem on our motors and those claiming it is over blown or not really a problem. The question really is, are you willing to take the chance? It's a $2-3k ($1k parts if you DIY) preventative repair to prevent a potentially 10k-15k+ repair. Choose based on what your gut tells you and be happy.

[tlow98]

Originally Posted by rcracin

Compression test came back as in ok across all 8 cylinders? That motor has got to be tired. The compression is probably lower than that of a motor with much less miles. I suggest preventative maintenance before risking blowing it.

What? What kind of preventative maintenance could he do that would refresh a motors compression that isn't a full rebuild? Any refresh you're referring to would equal or exceed the cost of a used motor.

When you combine this with the fact that BMWs M motors are notorious for 200k miles with little effort I'd say the OP would be throwing away money by refreshing anything other than rod bearings.

Statements like "got to be tired" are ridiculous.