[andreu12qw]

I wouldn't tell them you have a tune.

[Mean E92]

I'm one of the victims of the rod bearing failure. I had JB4, intake, chargepipe and a dp. I'm still not sure what happened exactly but my theory is that when my belt slipped because of the OFHG leak, the belt was sucked into the front main which then sucked into the oil pickup tube and the engine lost oil pressure for a slight moment which caused 2 of my bearings to spin. Gonna do a tear down of the old engine but not anytime soon. Whole thing costed me $11k. I had no choice but to fix it because the car is financed. I cannot stress how important that $5 gasket is to fix. Huge design flaw by BMW to not put a blockplate behind the front main. I owned the car since 60k miles and who knows if the oil was changed regularly. Huge financial mistake by me to get one of these cars without an extended warranty from BMW.

[Mean E92]

Originally Posted by dleccord

This topic is really concerning. If my car still runs with tune, can I still get after market warranty? Will they cover rod bearings and engine replacements?

If a rod bearing has slipped, then it's too late to replace them because there would be too much clearance. I wen't through all this and went with a used engine instead. The rebuild consist of a lot of machine work which turned out to be more expensive.

[indyn]

Originally Posted by Mad E92

I'm one of the victims of the rod bearing failure. I had JB4, intake, chargepipe and a dp. I'm still not sure what happened exactly but my theory is that when my belt slipped because of the OFHG leak, the belt was sucked into the front main which then sucked into the oil pickup tube and the engine lost oil pressure for a slight moment which caused 2 of my bearings to spin. Gonna do a tear down of the old engine but not anytime soon. Whole thing costed me $11k. I had no choice but to fix it because the car is financed. I cannot stress how important that $5 gasket is to fix. Huge design flaw by BMW to not put a blockplate behind the front main. I owned the car since 60k miles and who knows if the oil was changed regularly. Huge financial mistake by me to get one of these cars without an extended warranty from BMW.

Your rod bearing failure is caused by a serpentine belt that slipped because of OFGH leak. Nothing to do with actual engine defect of the N55 like the e9x series BMW M3.

I been running this car since 72k miles, at 106k miles, only replaced HFPF, OFGH gasket, oil pan gasket, coolant reservoir.
Preventive maintenance with Water pump and thermostat. Belt and pulley

Have Cobb PTF tune, catted dp, chargepipe and intercooler.

Used Factory OEM oil (not bad)
Castor 0W30 European formula - more chatter but revs nice.
Motul - Motor didn't like it
Liquid Moly 5w30 - The best

Recently fixed leak between DP and exhaust, tightened the DP bolt little more. Made a huge difference in terms of boost, rev and pick up.

N55 is a stout engine AFAIK. Gives amazing power and excellent gas mileage

[Lincoln Hawk]

I have a 2011 335i 83k miles completely stock no mods WITH A SPUN ROD BEARING! No belts slipped or anything like that just spun a bearing like all the others. I am getting the motor replaced by BMW but I am afraid to keep the car after that because im afraid of what is causing this issue and no way can I afford to have this happen again. Any info on why and is the n55 defective?

[rich_mane]

I mean, this isn't a common failure on the N55. It's not easy to pinpoint the exact cause because we don't have a complete history of each and every car's past maintenance and repairs. You never know what could have been done to that motor in the past which shortened it's lifespan (lack of maintenance or sub-par repair jobs, who knows.)

I just cross my fingers and hope I don't run into any problems like this. I'm at 97k miles now and have been diligent with my maintenance and upkeep since I bought the car at 50k.

[Lincoln Hawk]

I am wondering about the new motor I am getting now and what oil to run. I know I will be doing 3k mile oil changes for sure.

[Welcome to NBA Jam]

From this thread, the most important preventative maintenance you can do is promptly addressing oil leaks at the front of the engine and replacing your belt & tensioner at any sign of contamination or pulley wobble.

Due to the front crank seal design, a snapped belt is a catastrophic failure on our engines.

[JuniorB]

The belt is sucked in by the crank destroying the seal, in which oil pours out of it, The belt also gets caught in the gear and chain, other than that, it's leaking injectors that thins out the oil. If no one has updated injectors, it's a good idea to stay on top of oil samples. A $25 kit is a lot less that a $10k motor job.

[nojeans]

lucky me i do the following parts replacement but no engine fault
i drive everyday back to work and now reach 135,000km

valve cover gasket replace
spark plug and coil replace
DCT oil pan replace
wideband exhaust sensor first bank
high pressure fuel pump
low pressure fuel pump
fuel regulator
water pump
thermostat
upper water hose, upper water hose, turbo electric valve
expansion tank
vacuum valve
belt, belt tensioner, pulleys
outer oil filter housing gasket replace
DCT oil pan, DCT oil filter, DCT clutch filter replace
Oil filter housing gasket replace (near engine one)
cylinder head gasket replace + vanos recall
DCT RPM sensor replace <- costed US$3000
Engine mount
seat belt handover
front hub bearing
starter
radiator
throttle body
front/rear engine camshaft seal
transmission wiring harness
DCT oil pan
DCT hydraulic cover + gasket
outer oil filter housing gasket
rear ABS sensors
injector x 6
valvetronic motor + gasket
cam position sensors x 2
valve cover gasket
spark plug recess gasket x 3
door latch x 2
valve cover <- due to my mistake destroy screw thread
engine hydraulic valve
vanos solenoid valve gasket x 2
expansion tank <- cause my body weight on it
transmission mount

I'm happy with this car because the fuel consumption and handling. no modification on the engine, only change the ohlins coilover, M3 front/ear control arm, M3 rear subframe bushing

regular oil replace every 5000km

[Jeyoller]

Originally Posted by nojeans

lucky me i do the following parts replacement but no engine fault
i drive everyday back to work and now reach 135,000km

valve cover gasket replace
spark plug and coil replace
DCT oil pan replace
wideband exhaust sensor first bank
high pressure fuel pump
low pressure fuel pump
fuel regulator
water pump
thermostat
upper water hose, upper water hose, turbo electric valve
expansion tank
vacuum valve
belt, belt tensioner, pulleys
outer oil filter housing gasket replace
DCT oil pan, DCT oil filter, DCT clutch filter replace
Oil filter housing gasket replace (near engine one)
cylinder head gasket replace + vanos recall
DCT RPM sensor replace <- costed US$3000
Engine mount
seat belt handover
front hub bearing
starter
radiator
throttle body
front/rear engine camshaft seal
transmission wiring harness
DCT oil pan
DCT hydraulic cover + gasket
outer oil filter housing gasket
rear ABS sensors
injector x 6
valvetronic motor + gasket
cam position sensors x 2
valve cover gasket
spark plug recess gasket x 3
door latch x 2
valve cover <- due to my mistake destroy screw thread
engine hydraulic valve
vanos solenoid valve gasket x 2
expansion tank <- cause my body weight on it
transmission mount

I'm happy with this car because the fuel consumption and handling. no modification on the engine, only change the ohlins coilover, M3 front/ear control arm, M3 rear subframe bushing

regular oil replace every 5000km

Did all of these parts failed or some of them were preventive maintenance? This looks like a long list for a car that is only 84k miles according to google's conversion from KM to Miles.

[Lincoln Hawk]

Originally Posted by JuniorB

The belt is sucked in by the crank destroying the seal, in which oil pours out of it, The belt also gets caught in the gear and chain, other than that, it's leaking injectors that thins out the oil. If no one has updated injectors, it's a good idea to stay on top of oil samples. A $25 kit is a lot less that a $10k motor job.

Would I have know if the belt slipped or would it just run normally until it blew the rod bearing? Also the n54 had leaky injectors also and they dont have nearly as many reported rod bearing failures why is it mostly n55s? Im just trying to wrap my head around this because even with a new motor im wondering if i should keep the car or trade it in befor it happens again

[rich_mane]

You would know if the belt was slipping, but you should be able to at least get a rough idea of what condition the belt is in by just looking at it. Any cracks or frays and you should just replace it.

Did you have any maintenance done or oil leaks fixed before this happened?

[JETmn]

Originally Posted by Lincoln Hawk

Would I have know if the belt slipped or would it just run normally until it blew the rod bearing? Also the n54 had leaky injectors also and they dont have nearly as many reported rod bearing failures why is it mostly n55s? Im just trying to wrap my head around this because even with a new motor im wondering if i should keep the car or trade it in befor it happens again

I think you are blowing this out of proportion. The number of issues brought up on this forum are still easily single digits, I think around 5. This is an epidemic or some major issue. Who knows what has happened to those cars as most aren't the original owner.

[mxchris727]

The problem with the oil analysis is that it's not going to tell you anything about the rod bearings. Unlike previous BMW engines, the N55 uses lead-free bearings to cope with EU environmental standards and the repeated stop-starts.

My bet would be on the new bearing material wearing out faster than lead or being hyper-sensitive to the sulfur content in our fuel. With direct injectors, there's more fuel-oil dilution.

[Lincoln Hawk]

Originally Posted by rich_mane

You would know if the belt was slipping, but you should be able to at least get a rough idea of what condition the belt is in by just looking at it. Any cracks or frays and you should just replace it.

Did you have any maintenance done or oil leaks fixed before this happened?

Yes 5000 miles before thiS I had the oil filter housing gasket replaced by the dealer.

[rich_mane]

Originally Posted by Lincoln Hawk

Yes 5000 miles before thiS I had the oil filter housing gasket replaced by the dealer.

If the tech that did that repair wasn't careful they can introduce coolant or debris directly into the filtered oil passage which goes directly into the engine. Every N55 I've heard of failing has either just recently had the oil filter housing gaskets done, or let the leak go on so long that coolant and oil ended up mixing.

When you get the new motor put in, you really shouldn't even have to worry about those oil filter gaskets for at least a good couple years. When it comes time, make sure it's done properly and you aren't likely to run into a problem. The N55 has really proven itself pretty reliable so far (at least in my experience.)

[BoosTonian]

Tech I know had his bearings spin on his n55, now he’s dealing with a customers n55 with a spun bearing ...both cars were stock and at ~66k miles. No leaks or belt issues.

I just hope nothing happens to mine.

[Lincoln Hawk]

[QUOTE=rich_mane;22321927]If the tech that did that repair wasn't careful they can introduce coolant or debris directly into the filtered oil passage which goes directly into the engine. Every N55 I've heard of failing has either just recently had the oil filter housing gaskets done, or let the leak go on so long that coolant and oil ended up mixing.

When you get the new motor put in, you really shouldn't even have to worry about those oil filter gaskets for at least a good couple years. When it comes time, make sure it's done properly and you aren't likely to run into a problem. The N55 has really proven itself pretty reliable so far (at least in my experience.)[/

its crazy I bought this car because I thought the n55 would be more reliable than the n54

[Jeyoller]

Originally Posted by Lincoln Hawk

its crazy I bought this car because I thought the n55 would be more reliable than the n54

Literary the same thing i thought.... hopefully if this happens it'll happen under my warranty terms and ill be ok

[rich_mane]

I mean, regarding everything that has been said here, it doesn't seem like this is a common issue and can be mostly be avoided with proper maintenance.

I bought the N55 for the reliability as well and I have to say I'm damn happy with it.

[Lincoln Hawk]

Originally Posted by rich_mane

I mean, regarding everything that has been said here, it doesn't seem like this is a common issue and can be mostly be avoided with proper maintenance.

I bought the N55 for the reliability as well and I have to say I'm damn happy with it.

Thats good to hear hopefully my new motor will be better than the first