[RyanGMW]

I will chime in here. 13yr BMW master tech and indy BMW shop owner. Here's my past 6 months experiences with N55 engines.
Started a small car lot, bought a 2012 X5 N55 with "engine noise" at 82k. Assumed belt tensioner or something. Nope. Spun rod bearing cyl #2. Replaced engine with used motor ($4400 used engine) and installed all new rod bearings and bolts to be safe with updated S55 numbered bearings- car happy and sold.
Then 1 month later, a new customer brings in 2011 335i N55 E90 with 98k on clock, just bought at some random used car lot- has knock. Spun bearing. Dealer wont help him (less than 24 hours of his ownership).
Customer brings in 2011 X5 3.5i for PPI. Road tested, full load at 4500rpm I hear a knock. Rev up in neutral back at the shop, 2k rpm- rod knock. Pull out oil filter, full of metal shavings. Tell customer not to buy it. He brings me another X5 N55 today, pulled filter to see that one and it was full of shavings too but no noise (92k dealer maintained at 8-10k intervals).
Last week another shop towed in a 2011 X5 with N55 not running. They replaced a bunch of parts to no avail. Finally figured out DME had failed and wouldn't fire the injectors or coils. $2500 later it runs again and customer wants to dump it and run.
I Bought another N55 X5 with cyl #6 misfire and air plausibility codes. Removed valve cover after extensive time and testing to check valvetronics. Camshafts are rusted and lobes are worn to point of not opening valves at idle- replaced both camshafts, and then shortly after the valvetronics motor failed. back apart again....
In my recent experience, The N55 is a fragile and dangerous engine to own past 80k. I owned a 2012 X5 from 19k miles to 95k miles and it had its share of issues (57k OFHG failed, 59k valvetronics motor failed, 84k PCV/valve cover failed). I have a 2015 435i currently and it scares me to think of owning it long term... I know I only seen broken cars as thats what I fix for a living so maybe there are bunch of N55 success stories out there, but lately they seem to be failing left and right, maybe someone can encourage me that its only a temporary wave but my local dealers refer to the N55 as "Total Junk" and they see tons of rod bearing failures there and wont help most customers!

[bqik]

267000km here 2014 N55.

MPPK since 40.000km.

no oil consumption between oil changes : 15000km.

regards

[Polo08816]

Originally Posted by RyanGMW

I will chime in here. 13yr BMW master tech and indy BMW shop owner. Here's my past 6 months experiences with N55 engines.
Started a small car lot, bought a 2012 X5 N55 with "engine noise" at 82k. Assumed belt tensioner or something. Nope. Spun rod bearing cyl #2. Replaced engine with used motor ($4400 used engine) and installed all new rod bearings and bolts to be safe with updated S55 numbered bearings- car happy and sold.
Then 1 month later, a new customer brings in 2011 335i N55 E90 with 98k on clock, just bought at some random used car lot- has knock. Spun bearing. Dealer wont help him (less than 24 hours of his ownership).
Customer brings in 2011 X5 3.5i for PPI. Road tested, full load at 4500rpm I hear a knock. Rev up in neutral back at the shop, 2k rpm- rod knock. Pull out oil filter, full of metal shavings. Tell customer not to buy it. He brings me another X5 N55 today, pulled filter to see that one and it was full of shavings too but no noise (92k dealer maintained at 8-10k intervals).
Last week another shop towed in a 2011 X5 with N55 not running. They replaced a bunch of parts to no avail. Finally figured out DME had failed and wouldn't fire the injectors or coils. $2500 later it runs again and customer wants to dump it and run.
I Bought another N55 X5 with cyl #6 misfire and air plausibility codes. Removed valve cover after extensive time and testing to check valvetronics. Camshafts are rusted and lobes are worn to point of not opening valves at idle- replaced both camshafts, and then shortly after the valvetronics motor failed. back apart again....
In my recent experience, The N55 is a fragile and dangerous engine to own past 80k. I owned a 2012 X5 from 19k miles to 95k miles and it had its share of issues (57k OFHG failed, 59k valvetronics motor failed, 84k PCV/valve cover failed). I have a 2015 435i currently and it scares me to think of owning it long term... I know I only seen broken cars as thats what I fix for a living so maybe there are bunch of N55 success stories out there, but lately they seem to be failing left and right, maybe someone can encourage me that its only a temporary wave but my local dealers refer to the N55 as "Total Junk" and they see tons of rod bearing failures there and wont help most customers!

The N55 is probably one of the most common BMW engines out there for F chassis vehicles.

I have 105,000 miles on mine and those include track miles. No major issues so far. I've had the OFHG and oil pan gasket replaced under the extended warranty.

[arhoads335i]

On facebook I hear about this problem a lot on the E chassis cars.
Just change your oil
keep it topped off
Be nice to it when its cold
Get an intercooler (less prone to knock)
Use good gas (less prone to knock)
Use liqui moly ceratec

[upsidedownfunnel]

Originally Posted by RyanGMW

I will chime in here. 13yr BMW master tech and indy BMW shop owner. Here's my past 6 months experiences with N55 engines.
Started a small car lot, bought a 2012 X5 N55 with "engine noise" at 82k. Assumed belt tensioner or something. Nope. Spun rod bearing cyl #2. Replaced engine with used motor ($4400 used engine) and installed all new rod bearings and bolts to be safe with updated S55 numbered bearings- car happy and sold.
Then 1 month later, a new customer brings in 2011 335i N55 E90 with 98k on clock, just bought at some random used car lot- has knock. Spun bearing. Dealer wont help him (less than 24 hours of his ownership).
Customer brings in 2011 X5 3.5i for PPI. Road tested, full load at 4500rpm I hear a knock. Rev up in neutral back at the shop, 2k rpm- rod knock. Pull out oil filter, full of metal shavings. Tell customer not to buy it. He brings me another X5 N55 today, pulled filter to see that one and it was full of shavings too but no noise (92k dealer maintained at 8-10k intervals).
Last week another shop towed in a 2011 X5 with N55 not running. They replaced a bunch of parts to no avail. Finally figured out DME had failed and wouldn't fire the injectors or coils. $2500 later it runs again and customer wants to dump it and run.
I Bought another N55 X5 with cyl #6 misfire and air plausibility codes. Removed valve cover after extensive time and testing to check valvetronics. Camshafts are rusted and lobes are worn to point of not opening valves at idle- replaced both camshafts, and then shortly after the valvetronics motor failed. back apart again....
In my recent experience, The N55 is a fragile and dangerous engine to own past 80k. I owned a 2012 X5 from 19k miles to 95k miles and it had its share of issues (57k OFHG failed, 59k valvetronics motor failed, 84k PCV/valve cover failed). I have a 2015 435i currently and it scares me to think of owning it long term... I know I only seen broken cars as thats what I fix for a living so maybe there are bunch of N55 success stories out there, but lately they seem to be failing left and right, maybe someone can encourage me that its only a temporary wave but my local dealers refer to the N55 as "Total Junk" and they see tons of rod bearing failures there and wont help most customers!

I've found that regular maintenance will usually reward the owner of some German cars. I don't think it's any accident that you had cars that failed right away. They were probably just not maintained well and were sold after some damage was discovered.

With how common the N55 is, I feel like any widespread issues would be pretty well known by now.

[XutvJet]

It's pretty well know that the pre-2013/2014 N55s had some rod bearing failures. I believe all 2014+ N55s use the more robust S55 rod bearings and rods.

If you want to be really nice to your rod bearings, let your oil get up to temp (180+ degrees) before going full throttle, especially in a taller gear.

[Tchao]

Originally Posted by RyanGMW

I will chime in here. 13yr BMW master tech and indy BMW shop owner. ... I know I only seen broken cars as thats what I fix for a living so maybe there are bunch of N55 success stories out there

Hey Ryan, good to see you here from the R3v days.
I think this is a case of doctor/disease. You only see the worse and broken.

Like others have said, the N55 engine is so prolific that you are bound to see more N55 problems by default since its everywhere, and secondly, if there was a common weakness, it will be common documented failures everywhere.

My N55 is flirting with 100k now, and its just the common BMW crap since the M50 like OFHG and coolant lines.

[yas_e92]

For anyone that’s curious about N55 rod bearings or engine failures I myself have had my 2011 E92 335xi N55 engine hydrolock due to a Fuel injector malfunction causing fuel and oil to mix and a rod bearing or piston flew out the block.. fortunately this happened 3-4 weeks after buying the car from a BMW dealership (bought at 55k miles) so they covered the new engine swap, the whole process cost me about $100-$200. The car was completely stock and barely driven hard.
Since then I’m now at 156k miles on the car, 90k miles on the new motor with jb4+MHD bef, BMS Intake, ER fmic, ER chargepipe, fuel it stage 2+ lpfp, and everything has been functioning smoothly.

Overal I think keeping fuel injectors, spark plugs, and coil pack up to date can make a huge difference.

[F30ed]

Originally Posted by RyanGMW

...testing to check valvetronics. Camshafts are rusted and lobes are worn to point of not opening valves at idle...

RyanGMW, as 13yr BMW master tech, do you have an theory what may have caused rust on Camshafts and eccentric? They are constantly sprayed with oil, aren't they? Then how come...

[EmanueleTra]

[IMG][/IMG]
So my mechanic told me that the car might last 1 week or could last 5 years that the crankshaft is lightly scratched I just wanted to know if by the picture you guy can tell me if you think I should just switch the engine or any suggestions in what I should do

[n55david]

Originally Posted by EmanueleTra

[IMG][/IMG]
So my mechanic told me that the car might last 1 week or could last 5 years that the crankshaft is lightly scratched I just wanted to know if by the picture you guy can tell me if you think I should just switch the engine or any suggestions in what I should do

those pics tell us nothing

[n55david]

Originally Posted by EmanueleTra

[IMG][/IMG]
So my mechanic told me that the car might last 1 week or could last 5 years that the crankshaft is lightly scratched I just wanted to know if by the picture you guy can tell me if you think I should just switch the engine or any suggestions in what I should do

so.. everything that would tell you anything is covered by the rods and main caps. other than seeing the journals and the bearings etc for both the rods and main caps we can't tell you anything.

I tried to respond to your PM but you have it set to not receive messages.

[thejeremyman9]

The rod cap just seems to show that you might have spun a bearing or at least somehow overheated one. Unless there is another explanation for the discoloration...

[harkes]

Rule of thumb - if you can feel the scoring with a finger nails then it is scrap metal.

[Dr_BK]

From reading the entire thread, all I can say is your N55s have been angels to you. I am on my third N55 engine with bearing problems. Down here in Nigeria we just say "the engine has hooked". I never had the knock and exploding sound people have complained of. Mine just during normal drive just goes off and rolls to a stop and that's it. No crank or feels like a dead battery. You get a 22 socket wrench and can't turn the crankshaft.

Engine hook as we call it is the biggest BMW problems here in Nigeria. As we speak my N55 is in the workshop out of the car being coupled back together.

[Polo08816]

Just checking in. I'm at 141,000 miles on my N55 (stock tune) with a lot of track miles.

I do oil changes every 5,000 miles although the shop I go to recommends every 2,500 miles during oil change intervals that involve track usage.

I currently use Castrol Edge 5w-40 but have used Mobil 1 0w-40 and Castrol Edge 0w-40 in the past.

[1988]

Originally Posted by Dr_BK

From reading the entire thread, all I can say is your N55s have been angels to you. I am on my third N55 engine with bearing problems. Down here in Nigeria we just say "the engine has hooked". I never had the knock and exploding sound people have complained of. Mine just during normal drive just goes off and rolls to a stop and that's it. No crank or feels like a dead battery. You get a 22 socket wrench and can't turn the crankshaft.

Engine hook as we call it is the biggest BMW problems here in Nigeria. As we speak my N55 is in the workshop out of the car being coupled back together.

PWG version?

[thejeremyman9]

Originally Posted by Dr_BK

From reading the entire thread, all I can say is your N55s have been angels to you. I am on my third N55 engine with bearing problems. Down here in Nigeria we just say "the engine has hooked". I never had the knock and exploding sound people have complained of. Mine just during normal drive just goes off and rolls to a stop and that's it. No crank or feels like a dead battery. You get a 22 socket wrench and can't turn the crankshaft.

Engine hook as we call it is the biggest BMW problems here in Nigeria. As we speak my N55 is in the workshop out of the car being coupled back together.

Have you ever done an oil analysis? There seems to be an outside contributing factor... maybe if conditions are very dusty, oil contamination or something? I think you are on the far end of the spectrum not everyone else who isn't locking up engines. PWG bearings could also be a factor, but even still

[F32Fleet]

Scuttlebutt with the N55 is that it is supposedly susceptible to oil starvation under certain track conditions due to the design of the oil pan. Perhaps the pan on the N55 M2's is different and worth looking into.

[Polo08816]

Originally Posted by F32Fleet

Scuttlebutt with the N55 is that it is supposedly susceptible to oil starvation under certain track conditions due to the design of the oil pan. Perhaps the pan on the N55 M2's is different and worth looking into.

It is different and it's certainly worth looking into if you're going to be running stickier tires than 200TW tires.

Those oil sump systems in M cars will be able to sustain normal oil pressure under a sustained 1.3G.

[Eschmacher]

The M2 N55 has the same pan and pickup system as the S55. It is certainly something you can do to the N55, but it's not cheap to get the parts. $1k for the pan and about $1600 for the pump/pickup. Bimmerworld sells the retrofit, look up "S55 Oil Pump Upgrade" on their site.

[Dr_BK]

Originally Posted by 1988

PWG version?

yes it is PWG.