[Cdsmith235i]

There's a long story here so prepare yourself:

2015 M235i Zf8 RWD
49k miles on the clock 3 months out of warranty time period at the time of failure.
Running DINAN stage 3, fmic,intake, exhaust no DP.
Oil changes every 5k miles with liqui molly 5w-40


After some spirited driving one day the car started making light ticking noise around 3k rpm I immediately parked the car and made an appointment with the local BMW dealership, the car sat for few weeks I live about 35 minutes from the dealership I was driving the car at very low rpm 1000-1500 the entire way vehicle suddenly surges I hear a belt squeal and motor completely does won't turn over. After dealing with the car not going into neutral for an hour on the side of the highway I finally get it to Bmw and they confirm the motor has seized. After excruciating months of battling BMW North America and the dealership they tell me to shove it and they will not be offering any assistance due to an independent shop doing oil changes (reputable local shop that holds the record for faster N54 in America), they deny the invoices and consider oil shavings in the motor to be an outside influence and an Act of god in their words. They did several maintenance items on the car during my ownership including oil filter housing, valve cover, full injector replacement, turbo oil lines and gave the car a clean bill of health 4K miles before motor failure. They never gave the car a true diagnosis besides metal shavings and seized I have no idea what actually caused the failure. so I'll inspect it when I swap the motor. Still don't know how they deny a complete motor failure at 49k miles and 3 months out of warranty! I've honestly lost brain cells taking this up the customer relations ladder.

I've come to the realization I'm on my own here after the whole ordeal. I plan on doing a swap with a used lower mileage motor I have access to a lift and will have some mechanics helping me as well as being inclined myself just never taken a motor as new as this. So here are my questions.

I've talked with a few motor builders and it's out of my budget being quoted anywhere from slighty upgraded to fully built at 15-25k.

I wanted to do a turbo/ fueling while I did the swap but holy crap it adds up and I don't want to be 15k into this and have another motor failure. I plan on switch to MHD and doing a custom tune with DP.

Reputable places to buy a replacement motor? I've got a quote from for $7500 at 30k miles with one year warranty. Too scared to buy an eBay motor.

Any tips for the actual swap there are zero DIY's out there on this, I see some special tools listed such as a engine from trans separator, on various repair data sources are these needed?

Is my turbo toast as well from the metal, how would I flush the system turbo/oil cooler?

I'll take any helpful tips or insight!

[IMG][/IMG][IMG][/IMG][IMG][/IMG]

[pikcachu]

when was the Oil filter housing gasket changed ?

see https://www.e90post.com/forums/showthread.php?t=1554479

[RoundelM3]

I'd say this looks like bearing failure due to loss of oil pressure - but you'd need to get a definitive root-cause for the failure. Dinan's parallel warranty might come into play, although I had their S3 tune in an N54-engined car and never had any issues.

[Cdsmith235i]

Originally Posted by pikcachu

when was the Oil filter housing gasket changed ?

see https://www.e90post.com/forums/showthread.php?t=1554479

About 6 moths prior to failure

[seansurfn2]

Originally Posted by Cdsmith235i

About 6 moths prior to failure

did this indy shop use only bmw oem filters? i know if they put in non oem there can be a loss of oil pressure. im surprised bmw didnt pull all codes to see what tripped.. theyll remain stored.. i had an n54 throw a rod. had knock codes. if i were you i would have been investigating a lot more. metal shavings usually is rod bearings but the squealing noise and belt sound is another thing.. i know how you feel.. 24 hrs after driving my car off a lot it happened to me.m 4 years later the lawsuit still stands..

[seansurfn2]

further noted i read that shop did oil lines.. its suspect that lack of oil pressure or oil caused this.. not questioning their work but mistakes happen unfortunately.. i got a motor used 7500 and 2500 labor for an n54.. its painful and set me back for years at the time.

[Feddersen]

Most likely rod bearing failure. I had the same at about 70k miles. It is not that uncommon for the N55.

But did you really expect them to pay? First of all you have a rev dependent ticking noise (= engine is source) and yet you tried to drive the car to the mechanic. You have modified your engine and did not service it at BMW. Even if the car was within warranty they wouldn’t pay.

[Aspen235]

Originally Posted by Feddersen

Most likely rod bearing failure. I had the same at about 70k miles. It is not that uncommon for the N55.

But did you really expect them to pay? First of all you have a rev dependent ticking noise (= engine is source) and yet you tried to drive the car to the mechanic. You have modified your engine and did not service it at BMW. Even if the car was within warranty they wouldn’t pay.

I thought the same, surprised that the OP is surprised that there is no coverage. You can add in non-BMW approved oil and unknown filters in the mix. I would think that the mods cancelled any engine warranty full stop.

[Cdsmith235i]

Originally Posted by Feddersen

Most likely rod bearing failure. I had the same at about 70k miles. It is not that uncommon for the N55.

But did you really expect them to pay? First of all you have a rev dependent ticking noise (= engine is source) and yet you tried to drive the car to the mechanic. You have modified your engine and did not service it at BMW. Even if the car was within warranty they wouldn't pay.

The sound did not sound internal at all. I literally make my living off inspecting cars for such things. Oil changes were done with hengst oem filters. I was running liqui molly which is pretty reputable and a lot of owners choice. They had the car 4K miles before the failure for a valve cover and wheel bearing and gave the car a clean bill of health. I provided all invoices with mileage and dates of oil changes.they did a few of the oil changes I did twice as many as are standardly recommended, I understand why they didn't but it's obviously not a failure of maintenance on my part and they know the car very well, honestly the car has been a pain in the ass they did tons of warranty work on the car it's been to there at least 8 times sometimes months at a time.

[Cdsmith235i]

Originally Posted by seansurfn2

further noted i read that shop did oil lines.. its suspect that lack of oil pressure or oil caused this.. not questioning their work but mistakes happen unfortunately.. i got a motor used 7500 and 2500 labor for an n54.. its painful and set me back for years at the time.

Oil lines were done 6-7 months before failure I think the affects would have happened sooner if it was related to install but possible.

[aerobod]

With the Dinan tune, there is no point in trying for goodwill from BMW, as the engine is modified to run outside their design limits. Dinan would be the only course for warranty coverage.

[Feddersen]

Originally Posted by Cdsmith235i

The sound did not sound internal at all. I literally make my living off inspecting cars for such things. Oil changes were done with hengst oem filters. I was running liqui molly which is pretty reputable and a lot of owners choice. They had the car 4K miles before the failure for a valve cover and wheel bearing and gave the car a clean bill of health. I provided all invoices with mileage and dates of oil changes.they did a few of the oil changes I did twice as many as are standardly recommended, I understand why they didn't but it's obviously not a failure of maintenance on my part and they know the car very well, honestly the car has been a pain in the ass they did tons of warranty work on the car it's been to there at least 8 times sometimes months at a time.

As I said it is most likely a rod bearing failure. I can tell that I maintained my car the same way except that all oil changes were done by BMW and also way before the service indicator said it had to be done. The car was/is 100% stock. Yet is seized the engine. I however got it fully covered by BMW Germany even though it was 2½ years overdue.

BMW changed the construction of the bearings in the B58 engine compared to the N55 and I guess there is a reason for it. My wife wanted an M235i or M240i and due to the experience of the N55 engine in my car we decided for the M240i and to be sure we knew the full history we decided for a new one. If I was in your shoes I would try to either sell the car with a broken engine and don’t look back to the N55 or get it fixed with a new engine and forget anything about tuning it and still have it serviced more frequently than recommended. You should also replace all parts that have been in contact with the oil.

BMW btw inspected my car for any mods before they even considered looking at the engine issue.

[XutvJet]

Originally Posted by Feddersen

As I said it is most likely a rod bearing failure. I can tell that I maintained my car the same way except that all oil changes were done by BMW and also way before the service indicator said it had to be done. The car was/is 100% stock. Yet is seized the engine. I however got it fully covered by BMW Germany even though it was 2½ years overdue.

BMW changed the construction of the bearings in the B58 engine compared to the N55 and I guess there is a reason for it. My wife wanted an M235i or M240i and due to the experience of the N55 engine in my car we decided for the M240i and to be sure we knew the full history we decided for a new one. If I was in your shoes I would try to either sell the car with a broken engine and don’t look back to the N55 or get it fixed with a new engine and forget anything about tuning it and still have it serviced more frequently than recommended. You should also replace all parts that have been in contact with the oil.

Your failed 335i N55 pre-dated 2014. There was a rod bearing change at some point in the 2013 model year. All 2014+ N55s, including the N55 in the M235, use the same rod bearings as used in the M2/M3/M4 S55 motors. The 2014+ N55s also use the same S55 connecting rods as well. The M235 N55 also uses the same forged crank as the N55 in the M2. All other N55s use cast cranks.

Now this isn't to say that M235 N55s haven't had rod bearing failures, but it is not very common. The most common N55s with rod bearing failures are the pre-2014 N55s. FYI, there are rod bearing failures reported for B58s too.

Typically a rod bearing failure in a turbo car is brought about by either not allowing the oil to get up to operating temp (180 degrees, ~10 minutes of driving) before hammering it or a massive knock event occurs and literally hits the piston and rod so hard that it hammers the rod right through the oil film between the rod and bearing and the bearing spins. Super knock is often brought about by going heavy throttle at a low rpm and in a tall gear. This puts massive load on the short block and boost often spike because the heavy load and make for an over-boost situation.

On turbo cars, you can be operating outside of factory safeguards if you've got a lot more extra power and the stock safeguards simply aren't quick enough to react.

[Feddersen]

The crankshaft if different but the bearing shells are the exact same: https://bimmercat.com/bmw/en/parts/f...ce/11247576714

[XutvJet]

Originally Posted by Feddersen

The crankshaft if different but the bearing shells are the exact same: https://bimmercat.com/bmw/en/parts/f...ce/11247576714

That's not a BMW site. Try realoem.com and see for yourself.

[Feddersen]

It is the exact same catalog - ETK = ErsatzTeileKatalog. For realoem you have the same part here: https://www.realoem.com/bmw/enUS/par...&q=11247576714 and the same bearing shell is even used in the M2 and actually also in the S55 engine of the M3/M4.

[Shovelman]

Is the engine really toast? If you can save it you will probably save money and you will not have anyone else problems under your hood. And lose the mods and just drive it modestly.

[XutvJet]

Originally Posted by Feddersen

It is the exact same catalog - ETK = ErsatzTeileKatalog. For realoem you have the same part here: https://www.realoem.com/bmw/enUS/par...&q=11247576714 and the same bearing shell is even used in the M2 and actually also in the S55 engine of the M3/M4.

Yes, BUT did you miss the part about the rod bearings being superseded after 9/12 or essentially the mid-2013 model year? Which, coincidentally is the start of the S55 motor production and when the N55s started using the revised bearings.

Also, a little research turns up that the cause of your 335 N55 failure was not exactly known because you said BMW replaced the motor without investigating it. Lastly, your failed N55 had the prior part number bearings. It's well known that the earlier gen N55s did occasionally have rod bearing failures. The newer gen motors can sometimes have rod bearing failures as well, but it typically occurs in modded cars and those driven in race situations (typically very high sustained g's and high rpms).

[Feddersen]

Last time I had my car in for service my mechanic had just changed all bearings in a S55 engine that had gone about 50k miles. He estimated the expected remaining lifetime for the bearings to be less than 6k miles. The history of that engine is however unknown. So even a production update of a part is no guarantee.

Regarding my engine we know for sure that is was the rod bearing that failed but we do not know the reason for the bearing to fail. I had managed to stop the car so fast that even though there was a hole in the block there was no oil spill. The rod was broken and popped out of the block and at the same time fixed to the crankshaft. So there was no doubt that the rod bearing failed. But again. We don’t know why the bearing failed. Even if BMW had investigated it they would not tell the reason.

The conversion with the reporting mechanic btw was a bit fun.
Mechanic: We found the reason for the engine fail.
Me: Ok. Tell.
Mechanic: Well. There is only one yellow part inside your engine and that is the rod bearing and that is normally placed in the bottom of the engine.
Me: I know.
Mechanic: Well. See. Right now it is located in the top of the engine in your oil filter…

However lets hope that OP comes back with the reason for the failure.

[seansurfn2]

can't believe it but i saw my old post here of me talking about a spun rod on an n54 i had.. now my n55 engine seized. happened shortly after a shop did the oil pan gasket... not sure if thats related but the car ran great up until after they did that service.. vanos errors happened right after and really rough idle.. low oil pressure code just before failure. it took me 5 years to recover from the n54 blowing up and 6 years later got some of it back after suiing the dealership. now im doing it again...