[SCS55]

I'm at 96,000 miles on a 2015 335i that I have owned since 28,000 and trying to keep this running for the long haul. Just finished my 12th oil change and send in a sample to Blackstone every other 5000 miles.
For those that experienced a spun bearing, was there any tell tale sign that an oil analysis would pick up? Or is it simply boom, it spins and that's it.
OCI 5000 miles with Castrol 5W 40 or LM 5W 40

[thejeremyman9]

Post your oil report. There's a few others around here, but you have to dig.

Usually you look for abnormally high copper and lead to see if there is premature bearing wear. But the absence of presence of those doesn't necessarily prevent you from, or cause you to, spin a bearing. Even with totally healthy bearings/oil system you can spin one if you do something like overrev, drive hard with cold oil, get a massive knock, etc.

[harkes]

This is not a common failure at all! Try not to worry and enjoy the car.

[F32Fleet]

Originally Posted by harkes

This is not a common failure at all! Try not to worry and enjoy the car.

+1

[cfm56d7b]

The excessive connecting rod bearing wear has been reported in 2013 vehicles with N55 engines. Just keep up with oil changes and enjoy every mile!

[XutvJet]

Originally Posted by SCS55

I'm at 96,000 miles on a 2015 335i that I have owned since 28,000 and trying to keep this running for the long haul. Just finished my 12th oil change and send in a sample to Blackstone every other 5000 miles.
For those that experienced a spun bearing, was there any tell tale sign that an oil analysis would pick up? Or is it simply boom, it spins and that's it.
OCI 5000 miles with Castrol 5W 40 or LM 5W 40

Your N55 has the upgraded rod bearings and forged rods from the S55 used in the M2C/M3/M4. The pre-2014 N55s don't have these upgrades and are more prone to spun rod bearings.

Usually when a rod bearing fails in the N55 or most any car, there is little warning, even with routine used oil analysis. With modded turbo cars, heavy knock can hammer the piston so hard that it pounds the rod through the protective oil film between the rod bearing and crankshaft. I can't say I've heard much in the way of spun rod bearings on modded 2014+ N55s. It can happen but it's rare.

[SCS55]

Originally Posted by XutvJet

Your N55 has the upgraded rod bearings and forged rods from the S55 used in the M2C/M3/M4. The pre-2014 N55s don't have these upgrades and are more prone to spun rod bearings.

Usually when a rod bearing fails in the N55 or most any car, there is little warning, even with routine used oil analysis. With modded turbo cars, heavy knock can hammer the piston so hard that it pounds the rod through the protective oil film between the rod bearing and crankshaft. I can't say I've heard much in the way of spun rod bearings on modded 2014+ N55s. It can happen but it's rare.

Good to know. I'm also a 10/2014 build date if it makes any difference. Basically a late year build.

[XxThe_RemedyXx]

Mine is a 1/2014 build. You guys think I should be worried?

[harkes]

Originally Posted by XxThe_RemedyXx

Mine is a 1/2014 build. You guys think I should be worried?

Yes, better part out before its too late. I'll take it off your hands- CHEAP!

[Eschmacher]

Originally Posted by XutvJet

Your N55 has the upgraded rod bearings and forged rods from the S55 used in the M2C/M3/M4. The pre-2014 N55s don't have these upgrades and are more prone to spun rod bearings.

Usually when a rod bearing fails in the N55 or most any car, there is little warning, even with routine used oil analysis. With modded turbo cars, heavy knock can hammer the piston so hard that it pounds the rod through the protective oil film between the rod bearing and crankshaft. I can't say I've heard much in the way of spun rod bearings on modded 2014+ N55s. It can happen but it's rare.

When you say pre-2014, is that model year 2014, or build date?
For example, mine is a 2014 model but built 8/2013.

[XxThe_RemedyXx]

Originally Posted by harkes

Yes, better part out before its too late. I'll take it off your hands- CHEAP!

Noooooooo!!!!!

[XutvJet]

Originally Posted by Eschmacher

When you say pre-2014, is that model year 2014, or build date?
For example, mine is a 2014 model but built 8/2013.

2014 model year cars have the upgrades. If your N55 has an EWG then it has the upgrades.

[Eschmacher]

Originally Posted by XutvJet

2014 model year cars have the upgrades. If your N55 has an EWG then it has the upgrades.

Fantastic

[SCS55]

Originally Posted by XutvJet

2014 model year cars have the upgrades. If your N55 has an EWG then it has the upgrades.

I'm drawing a blank. EWG.... electronic waste gate?

[Munchi435i]

Originally Posted by SCS55

I'm drawing a blank. EWG.... electronic waste gate?

Yes

[zinner]

Lead in the oil is typical for bearing failure per blackstones comments. I have a 2015 335i and I usually have 1-3 ppm of lead in the oil which isn't normal over the last few years but its hard to be too concerned at those levels. From my internet research the M3 folks typically see 30-40 ppm when the bearings are spun or worn. If get a report in the double digits I will probably break into the bottom end and have a look.

Edit: corrected the element to lead from iron.

[SCS55]

Originally Posted by zinner

Iron in the oil is typical for bearing failure. I have a 2015 335i and I usually have 1-3 ppm of iron in the oil which isn't normal over the last few years but its hard to be too concerned at those levels. From my internet research the M3 folks typically see 30-40 ppm when the bearings are spun or worn. If get a report in the double digits I will probably break into the bottom end and have a look.

Interesting. Same year and model here. Last two of my UOA's shows 3 and 4 on the Iron levels. (1/2019 and 6/2019)..I'm waiting for the latest report from a sample sent in last week.
I cross checked the iron levels from my 2016 M3 and out of 6 samples covering 30,000 miles, the average Iron count is 3 ppm.

[zinner]

I was referring to the E9x M3's for the 30-40 ppm, didn't know the F8x's had bearing issues.

[joni_titi]

Originally Posted by zinner

Iron in the oil is typical for bearing failure. I have a 2015 335i and I usually have 1-3 ppm of iron in the oil which isn't normal over the last few years but its hard to be too concerned at those levels. From my internet research the M3 folks typically see 30-40 ppm when the bearings are spun or worn. If get a report in the double digits I will probably break into the bottom end and have a look.

My Blackstone report for a 2012 335i with 87 000 mile show level of iron of 20 ppm. Average value is 30 ppm, dont' know how Blackstone calculate their average value (by model year, by engine code) so it's hard to say if it's high or low. In their report Blackstone stated:

''Averages for the N55 are based on oil run for about 9,500
km. You ran this oil nearly that same interval, and wear metals are all either right in line with the averages or
else even better (see iron and copper). That shows healthy wear, and your engine looks great. A 6.2 TBN
shows active additive remaining (1.0 or below is low). No significant contamination noted.''

[F32Fleet]

Due to the plethora of misinformation on acceptable wear I'm forwarding this link.

If you're truly interested in the subject read the article.

https://bobistheoilguy.com/used-oil-...hat-is-normal/

[Boostedphil698]

If you are worried, find a good indy shop and have them install VAC coated bearings.

[JaredG_F30]

I plan on getting mine replaced at 100k miles. I'm just about to hit 85k. I also have Blackstone run an oil analysis every 10k miles. So far my reports show all levels are in the normal range. I also plan to have this car for the long haul and I've been tuned since about 37k miles so better safe than sorry.