[Pladi]

Originally Posted by Veilside

Hello all,

I would like to add some useful information into this thread since I also own a 2011 N55 335i with currently about 86 000 miles. My production date was 02/10 Munich, Germany. All stock. So far I have done two Blackstone Oil analysis.

The first oil analysis was done at 81 000 miles and came out pretty bad as the iron level was a little too high. It may be the cause long oil interval at around 7500 miles with the original 5w-30 BMW Oil, and also it was during winter times hence maybe the freezing cold start may have cause some harm here in Canada.

The second one was done at about 86 000 miles however was very good as all the metals were lower than average and the oil was changed at about 5000 miles. I was also using Liqui-moly 5w-40 during that time.

Maintenance done so far were:
- OFHG @ 81 000 miles
- Serpentine belt @ 81 000 miles
- Coolant expansion tank @ 81 000 miles
- Spark plugs @ 60 000 miles
- water pump @ 65 000 miles

Recall for VANOS bolt were done in 2014, and I am currently the 2nd owner. Car were always warmed up with the oil temp to 2 notches on the gauge before beating on it. Have been using 91 shell ever since I owned the car.

Question for you sir. Looks like for both oil changes you did not have to add any oil during the oil change interval of 9k miles. I know these motors burn oil. Some more than others. But to add nothing seems pretty extreme. For me i usually have to add half litre for 5000 km. So at 15 k km i would have added a liter and a half. (This amount depends on how hard i drive it too). So when u changed ur oil how much oil came out ? Do you ever measure that ?

[9krpmrx8]

Pladi,

My car has always eaten a quart every oil change. I monitor it constantly and keep it full. My best friend also has a 2011 335i with 100k on it and his has always consumed just as much.

[Veilside]

Originally Posted by Pladi

Question for you sir. Looks like for both oil changes you did not have to add any oil during the oil change interval of 9k miles. I know these motors burn oil. Some more than others. But to add nothing seems pretty extreme. For me i usually have to add half litre for 5000 km. So at 15 k km i would have added a liter and a half. (This amount depends on how hard i drive it too). So when u changed ur oil how much oil came out ? Do you ever measure that ?

Sorry I forgot to add, the 9k miles interval oil change I had to add about a quart of oil. While the 5k miles interval only burn about a bar on the oil level monitoring in iDrive so I did not bother adding it.

[SnapCoupe]

Originally Posted by fatty335

All - I have been reading up on this recently and some report similar failures immediately following an OFHG replacement. I suppose not draining the coolant and allowing it to dump into the crankcase could introduce enough coolant into the oil to cause an issue? Perhaps it is worth tracking how many of these happened around the same time as an OFHG replacement...just a thought. Other things that could be causal that are circulating around the forums:
- an overheating event (likely WP failure)
- tight factory bearing clearance exacerbated by increased power demand (tune)
- production/manufacturing change/part update
- long factory oil drain intervals

I had my OFHG, OCHG, waterpump, and thermostat all done about 4-5k miles before my motor went. Considering it was done all at once, I am pretty sure the coolant was drained before the OFHG was done. Figured it might just be worth mentioning.

[bbnks2]

Did any of these cars have a smfw?

[Pladi]

Originally Posted by bbnks2

Did any of these cars have a smfw?

I dont even think we have the information of what transmission type on each case.. Manual/Automatic.

Whats the relevance to the single mass fly wheel.

[bbnks2]

Originally Posted by Pladi

I dont even think we have the information of what transmission type on each case.. Manual/Automatic.

Whats the relevance to the single mass fly wheel.

Thrust bearing... if that wears out and locks up the crank will starve of oil.

[Pladi]

Originally Posted by bbnks2

Thrust bearing... if that wears out and locks up the crank will starve of oil.

hmm very interesting. Never knew that. I have owned alot of manual transmission cars never knew that. My BMW is automatic but i have always owned manual cars before and never heard of that. Very interesting.

People with the issue should chime.

[TZANIDO777]

Most likely spun a rod bearing over the weekend at Calabogie Motorsports Park. Started to hear a very loud metal clanking sound and cars oil temp went to 285 (water stayed at 206F max) before I had to call it quits and come into the pits. This is on a track only car for the past 4 years.

2011 135
N55 engine
Manual Transmission
Oil change interval every 20 hours for the last 4 years
First 2 years of track only was using oem 5W30 and then switched to Motul 300V 5W30 for remaining 2 years.
I am original owner - 31k miles mix of track and daily driving, 4k Track only, total 35k miles
FBO with MHD stage 2 OTS tune

May have over revved car during the first session on Saturday but the data suggests I did not go over 7K rpm. Problems started happening after this point.

Have not removed oil pan yet to inspect as I just back yesterday and doing some research now on my options. Car still turns on and runs but with a loud metal clanking noise.

Looking at the MMP rebuild option as it seems the most cost effective and would have a built motor. Could do a lot of the labor (removing and installing engine) myself.

[SnapCoupe]

Originally Posted by TZANIDO777

Most likely spun a rod bearing over the weekend at Calabogie Motorsports Park. Started to hear a very loud metal clanking sound and cars oil temp went to 285 (water stayed at 206F max) before I had to call it quits and come into the pits. This is on a track only car for the past 4 years.

2011 135
N55 engine
Manual Transmission
Oil change interval every 20 hours for the last 4 years
First 2 years of track only was using oem 5W30 and then switched to Motul 300V 5W30 for remaining 2 years.
I am original owner - 31k miles mix of track and daily driving, 4k Track only, total 35k miles
FBO with MHD stage 2 OTS tune

May have over revved car during the first session on Saturday but the data suggests I did not go over 7K rpm. Problems started happening after this point.

Have not removed oil pan yet to inspect as I just back yesterday and doing some research now on my options. Car still turns on and runs but with a loud metal clanking noise.

Looking at the MMP rebuild option as it seems the most cost effective and would have a built motor. Could do a lot of the labor (removing and installing engine) myself.

May not be a rod bearing given what you heard/saw when it happened. When mine went my temps were all nominal, there were no noises, the car just hesitated for a moment, and if I took my foot off the gas it wanted to die. Once I pulled over and turned it off, it wouldn't start again for about 30 minutes (It would crank, but it was VERY slow). After that, the car started and drove fine but I could something wasn't quite right. Lo and behold, the next morning the car developed a knock when I went to drive off.

[TZANIDO777]

Originally Posted by SnapCoupe

May not be a rod bearing given what you heard/saw when it happened. When mine went my temps were all nominal, there were no noises, the car just hesitated for a moment, and if I took my foot off the gas it wanted to die. Once I pulled over and turned it off, it wouldn't start again for about 30 minutes (It would crank, but it was VERY slow). After that, the car started and drove fine but I could something wasn't quite right. Lo and behold, the next morning the car developed a knock when I went to drive off.

What else do you think it could be? I had a few credible people look and listen to it at the track (one of which builds engines for S54 race cars) and they all pointed the finger to a spun bearing given the noise the car was making at idle and the overheating on track.

Not discrediting you by any means, just curious what you're thinking it could also possibly be. Do not mind getting additional opinions. (I understand there are a lot of variables involved)

Also, what did you end up doing? Repair? Rebuild? Swap engine?

[SnapCoupe]

Originally Posted by TZANIDO777

What else do you think it could be? I had a few credible people look and listen to it at the track (one of which builds engines for S54 race cars) and they all pointed the finger to a spun bearing given the noise the car was making at idle and the overheating on track.

Not discrediting you by any means, just curious what you're thinking it could also possibly be. Do not mind getting additional opinions. (I understand there are a lot of variables involved)

Also, what did you end up doing? Repair? Rebuild? Swap engine?

Pull your oil filter and shine a flash light at it. If its full of copper its more than likely the bearings. The only reason I mentioned it could've potentially been something else is mine was dead quiet when it happened. Also my knock was very faint and only noticeable when hovering the throttle at 2000-2500 RPM. The engine sounded totally normal at idle.

I ended up getting a new motor installed by the BMW dealer I work at after weighing all of my options and doing the math. I figured the car was worth keeping considering the money I had just put into it mod/maintenance wise, how its spec'd option wise, and the fact that my used motor options seemed to be a bit sketchy with what they came with.

[Ozzie335i]

Can a column be added indicating where the owners are located? Asking as I recall reading an article years ago stating that most engine wear occurs upon startup. Specifically when cold outside.

[Pladi]

Originally Posted by Ozzie335i

Can a column be added indicating where the owners are located? Asking as I recall reading an article years ago stating that most engine wear occurs upon startup. Specifically when cold outside.

Thats normal engine wear... bearings dont seize from normal engine wear. Spun bearing is a complete bearing failure. You would not get that on a normal operating engine if you started it in cold weather all year round day after day..

So cold weather is not the cause thats for sure.

[Ozzie335i]

Plaid, surely we can agree that in order to end up with a spun bearing there must be abnormal bearing wear of some kind. Otherwise what is the point of oil analysis, if not to identify bearing wear prior to a catastrophic bearing failure, thus a less costly repair can hopefully be made.

Unless it is known exactly what the cause of this is, you really can't make a blanket statement of what the cause isn't. I put the cold out there as starting an engine on a cold day can cause more wear.

As far as the guy with end caps, and seizure, that may or may not be related. I say that since that is the first I have heard of anybody here having that happen. He may have been unaware and one of the rod bearings disintegrated and got into the mains. I don't keep up on every thread, but id bet that engine probably isn't salvageable. Poor guy.

With P2, PI and 68 k miles, 10 or so with PI, I am scared. After all the money I have spent on upgrading this car I need a rebuild already? I may consider proactively swapping out the rod bearings.

[SnapCoupe]

Originally Posted by Ozzie335i

Plaid, surely we can agree that in order to end up with a spun bearing there must be abnormal bearing wear of some kind. Otherwise what is the point of oil analysis, if not to identify bearing wear prior to a catastrophic bearing failure, thus a less costly repair can hopefully be made.

Unless it is known exactly what the cause of this is, you really can't make a blanket statement of what the cause isn't. I put the cold out there as starting an engine on a cold day can cause more wear.

As far as the guy with end caps, and seizure, that may or may not be related. I say that since that is the first I have heard of anybody here having that happen. He may have been unaware and one of the rod bearings disintegrated and got into the mains. I don't keep up on every thread, but id bet that engine probably isn't salvageable. Poor guy.

With P2, PI and 68 k miles, 10 or so with PI, I am scared. After all the money I have spent on upgrading this car I need a rebuild already? I may consider proactively swapping out the rod bearings.

I have heard that the bearings are accessible through the oil pan from underneath the car and not that labor intensive to swap out. If you are worried about potential future issues with yours, I suggest looking into swapping them out just to be safe.

Also on that note, I was told by a few experience BMW techs that if I had not driven the car after it seized up on me and rather towed it to a shop, they could've swapped the bearings through the oil pan. What destroys the motor is driving with a spun bearing/rod knock and warping the crankshaft(?) journal IIRC. Figured I would at least leave that information here to see what you guys think.

[Ozzie335i]

Originally Posted by SnapCoupe

I have heard that the bearings are accessible through the oil pan from underneath the car and not that labor intensive to swap out. If you are worried about potential future issues with yours, I suggest looking into swapping them out just to be safe.

Also on that note, I was told by a few experience BMW techs that if I had not driven the car after it seized up on me and rather towed it to a shop, they could've swapped the bearings through the oil pan. What destroys the motor is driving with a spun bearing/rod knock and warping the crankshaft(?) journal IIRC. Figured I would at least leave that information here to see what you guys think.

I was hoping for such ease of access. Knew it was that way with American cars, but not these overpriced rides. For any issue with crank journals, I'd expect that the engine would have to come out for anything wrong with it. It most likely would be more of a situation of scoring that can not be machined as the main cause of said damage. Regardless, as you said SC, driving any distance with a rod bearing issue can be catastrophic. But we must first know it is anout to, or has occurred. With my car stereo jamming I fear that it could have a hiccup without me knowing. Oil analysis to be done soon.

[Pladi]

Originally Posted by Ozzie335i

Plaid, surely we can agree that in order to end up with a spun bearing there must be abnormal bearing wear of some kind. Otherwise what is the point of oil analysis, if not to identify bearing wear prior to a catastrophic bearing failure, thus a less costly repair can hopefully be made.

Unless it is known exactly what the cause of this is, you really can't make a blanket statement of what the cause isn't. I put the cold out there as starting an engine on a cold day can cause more wear.

As far as the guy with end caps, and seizure, that may or may not be related. I say that since that is the first I have heard of anybody here having that happen. He may have been unaware and one of the rod bearings disintegrated and got into the mains. I don't keep up on every thread, but id bet that engine probably isn't salvageable. Poor guy.

With P2, PI and 68 k miles, 10 or so with PI, I am scared. After all the money I have spent on upgrading this car I need a rebuild already? I may consider proactively swapping out the rod bearings.

You are thinking of swapping the rod bearings proactively ? MAn that doesnt sound like a good idea at all. If there is nothing wrong with your car just drive it. As you said we have no root cause so swapping bearings it doesn't mean now is fail proof. In fact the chances of an engine builder getting rod bearing clearances wrong especially non OEM is very high. Higher than not touching anything. This engine is not a chevy 350 block..

[9krpmrx8]

It's not a 350 but it's not a W16 either, BMW shops typically have a lot of experience replacing rod bearings. Yes there is some risk, but a competent tech can do it no problem.

[Welcome to NBA Jam]

Originally Posted by Pladi

You are thinking of swapping the rod bearings proactively ? MAn that doesnt sound like a good idea at all. If there is nothing wrong with your car just drive it. As you said we have no root cause so swapping bearings it doesn't mean now is fail proof. In fact the chances of an engine builder getting rod bearing clearances wrong especially non OEM is very high. Higher than not touching anything. This engine is not a chevy 350 block..

I agree. Swapping rod bearings when they're still working is an inherently risky procedure, and may not address the original problem itself.

If those who have had a bearing failure could also include the last 7 digits of their VIN, that would be helpful. We can get the actual build date and other pertinent information.

[Pladi]

Originally Posted by 9krpmrx8

It's not a 350 but it's not a W16 either, BMW shops typically have a lot of experience replacing rod bearings. Yes there is some risk, but a competent tech can do it no problem.

again you are missing the point.. You have a headache you take Tylenol and no more headache you are not dealing with the root cause. Your headache will return. If you know for sure that the bearings are bad thats when you do that type of work.. who here has proved that. So replacing bearings "proactively" does not necessarily solve the root cause. Your new bearings will have the same potential of failure if you have not dealt with the root cause..

[bbnks2]

Originally Posted by Pladi

again you are missing the point.. You have a headache you take Tylenol and no more headache you are not dealing with the root cause. Your headache will return. If you know for sure that the bearings are bad thats when you do that type of work.. who here has proved that. So replacing bearings "proactively" does not necessarily solve the root cause. Your new bearings will have the same potential of failure if you have not dealt with the root cause..

I see BMW spec'd these motors for rod bearing clearances of .00135". Most engine builders would spec a 20wt oil for that tight of a tolerance... S65 engines have the same type of pre-mature bearing wear with the same tight clearance spec and they change their bearings every 60k as a preventative measure. BMW is now putting 30wt oil into those motors vs their old recommendation of 60wt.

I think this may become a future recommendation with N55 motors too... Many engine builders are grinding down cranks and running .002" - .003" rod bearing clearances which is better suited to 40wt oils and high load engines. We very well could be seeing intermittent oil starvation causing bearing wear over time. Particularly, in left hand sweepers. Once the bearing get's worn down past its hard out layer, which we have seen plenty of motors show bearings down to the copper, they will over-heat and melt to the crank. Not much you can do about oiling except maybe run a thinner oil, but you can surely polish the crank and throw in new bearings in a few hours as a maintenance thing for <$150.

Changing rod bearings is not rocket science. I think we would see 100x more engines have this work done if it didn't involve so much work to get the oil pan off. Once the pan is off all you have to do is remove the rad caps and swap the bearings. There is nothing to "get wrong" except mixing up the rod caps or something. The only reason why rod bearing clearance would be out of spec is because you have a rotating assembly problem. This is hardly something someone swapping rod bearings should encounter, but it would damn nice to catch an out of spec rotating assembly before a seized motor!