Another Spun Crank Hub

[TurboM]

2016 M4 Non-ZCP
Manual Transmission
February 2016 build date
6k miles (half of which were highway cruising miles)
Unmodded
Never been over-revved, tracked, beaten on, etc.

I was driving fairly late at night on a straight rural road and pushed it a bit in 2nd and part of 3rd (i.e. flooring it for a couple gears) and shortly after letting off the throttle the CEL came on. I pulled over and used a bluetooth OBD scanner to pull the codes. The code tied back to cam timing (i.e. VANOS). I reset it and then proceeded to head back home but shortly after the CEL came back on, same code. I put the car in my garage for the night and returned the next morning to find the car took an extra second or 2 to turn over and was idling very bad and lumpy (obviously because the timing was off). I shut it down and had to wait until Monday to bring the car to the local dealer. Upon starting it again, I heard a metal thud under the hood right when it started, no idea what that was at this point. The car would fluctuate between idling perfectly fine and bad, not exactly sure why. I limped it to the dealer the following Monday morning and it’s been there ever since.

I spoke to the technician for a while about various things and he said the crank bolt was NOT loose at all when he inspected the car and it took a normal amount of forced to get it off. We looked over the motor together while it was pulled and disassembled and he pointed out the slight scoring on the nose of the crank where the hub and washer sit flush against it, obviously not a good sign. The crank hub was pretty much trashed, as expected.

So my practically brand new M4 has been sitting at a dealer for 2 weeks and with the motor out of the car in a what looks like a million pieces for the past week. After the PUMA case was opened a BMWNA regional engineer decided to just replace the damaged VANOS and crank hub components. No other information has been provided by BMWNA. I have no reason to think this isn't going to happen again sometime shortly after getting the car back. I opened up a case with BMW relations in an attempt to get them to consider buying the car back but they said since they are only replacing a few parts they would not be able to offer this to me, which I understand given it’s only a few parts and they're not replacing the motor. Now I have to anxiously drive what I feel is a $70k ticking time bomb. I honestly hope it happens again so I can get BMW to take the car back or lemon it. Fun times...

Update: Spoke to the shop foreman and apparently someone from BMW did come out to take a look at the motor and didn't see enough damage to warrant a replacement motor. I guess I refrain my original statement about BMWNA (I edited the section above), looks like it was just poor communication. He said they don't tell him what they feel caused the issue but his best guess was the crank bolt may have not been properly torqued from the factory, but who really knows (I think it's a design issue). Additionally, the tech said he ordered the replacement parts which have different part numbers than the original parts. Not sure which parts specifically, but I'll find out when I get the car back.

[Canuckles]

Sorry to hear about your troubles. Hopefully you can get some guidance and reassurance from the members on board. Good luck with your M.

[JamesGames]

On a revised bedplate build.. Hm.. good luck and hope you get the car back soon.

[JoeyBananas]

Sorry to hear, didn't 2016s have the "new bed plate" design

[TurboM]

Originally Posted by JoeyBananas

Sorry to hear, didn't 2016s have the "new bed plate" design

Looks like that theory is null and void.

[dmk08]

Originally Posted by JoeyBananas

Sorry to hear, didn't 2016s have the "new bed plate" design

Not all of them. But his built date is after the supposed Dec 2015 change over date.

Also a stock manual so there goes the "DCT Kickdown" theory.

[quattr0]

Sorry to hear OP. Understand you feel disappointed and wanted to vent but BMW will not do anything as the failing rate is fairly small according to forum posts.

Do what I did. Sell it and move to a better Platform. Notice capital P. Hint hint. Life is too short to waste time on it.

[dmk08]

Originally Posted by quattr0

Sorry to hear OP. Understand you feel disappointed and wanted to vent but BMW will not do anything as the failing rate is fairly small according to forum posts.

Do what I did. Sell it and move to a better Platform. Notice capital P. Hint hint. Life is too short to waste time on it.

Yeah Porsches never have problems...

[quattr0]

Originally Posted by dmk08

Yeah Porsches never have problems...

Here we go....;-)

Wonder who comes out on top with dependability record recently.

[dmk08]

Originally Posted by quattr0

Here we go....;-)

Wonder who comes out on top with dependability record recently.

Porsche is higher according to JD Power but BMW had a surprisingly good showing in 2016. BMW 7 Porsche 2. Power train wise they have the same score.

Haters will Hate indeed. "Move to a better Platform"

[Daxos]

Sorry to hear that TurboM. So they just replaced the broken parts and put the engine back together but have no real idea what caused the issue and addressed the underlying issue?

I'd be real concerned about the issue repeating itself in that case, too

[DavidGP]

OP, can you go into specifics on what happened. Did you downshift to 2nd and from what speed, what RPM did you shift into 3rd etc, powershift? If you want to reply by PM thats fine to.

[SakhirM4]

I sympathize with the OP, but don't think we are getting the whole story. What does "pushed it a little bit" mean? Money shift?

[TurboM]

Originally Posted by SakhirM4

I sympathize with the OP, but don't think we are getting the whole story. What does "pushed it a little bit" mean? Money shift?

Come on man. Read to post, never over-revved. Pushing it to me means flooring it through a gear or 2. I'll edit the original post to avoid future confusion.

[avantix]

Originally Posted by dmk08

Yeah Porsches never have problems...

[DonkeyKong]

Was the new bed plate design implemented on all builds, I thought I read the GTS and ZCP had the new bed plate.

[dr.mba]

Anyway you put it this is bad news. It's always been felt that the platform had an Achilles heel for "modding". Everyone seemed to be confident that the platform is stable if not tampered with. Manual was seemingly the safe bet so long as you didn't "money" shift. The modified bedplate was felt to be a solution to this that BMW never acknowledged to be. This seems to refute all of what we came to conclude in the past. Good luck OP with all of this. My heart is with you. Now I am going to have to push my car more often and make this happen before I run out of warranty!!

M

[dmk08]

Originally Posted by DonkeyKong

Was the new bed plate design implemented on all builds, I thought I read the GTS and ZCP had the new bed plate.

It was only marketed for those two but people have stated the part number for it in all motors changed in Dec 2015 I believe.

[CaryTheLabelGuy]

Op, sorry to hear about your SCH. I'm sure BMW will take care of everything. Would you mind post a shot of your build (found on the driver's door jamb sticker) and post the repair order? This will confirm the SCH and will be the first confirmed SCH on a post Dec 2015 S55.

As for the people saying that the new bedplate theory is out the window due to a supposed SCH on a post-DEC 2015 build, I wouldn't be so quick to pass judgement. Just because you have one known failure doesn't mean the whole theory is a bust; that's silly.

Let's wait for more info and an actual confirmation.

[TurboM]

Originally Posted by CaryTheLabelGuy

Op, sorry to hear about your SCH. I'm sure BMW will take care of everything. Would you mind post a shot of your build (found on the driver's door jamb sticker) and post the repair order? This will confirm the SCH and will be the first confirmed SCH on a post Dec 2015 S55.

As for the people saying that the new bedplate theory is out the window due to a supposed SCH on a post-DEC 2015 build, I wouldn't be so quick to pass judgement. Just because you have one known failure doesn't mean the whole theory is a bust; that's silly.

Let's wait for more info and an actual confirmation.

Repair order won't come until I pick the car up, probably sometime late next week. As far as posting a pic of the sticker in the door jamb, again I can't take any pics until I get the car back although I'm not sure what you're trying to get at here. What "confirmation" are you looking for? I can probably tell you whatever info you need without it (not trying to be condescending here ).

Honestly though, after speaking with the shop foreman and master tech for quite some time over the fast few days, in conjunction with knowing that the part numbers ordered vary from the originals, I'm leaning towards a design issue here and BMW is trying to correct it with some slightly improvised/improved parts as these failures surface. Until these supposed revised parts made it into the production builds, I'd be willing to bet that any and all M3/M4s are subject to this issue with the assistance of other variables. Just an opinion, everyone has their own at this point.

Also, I personally don't think this supposed "revised bedplate" has anything to do with preventing this issue as BMW motors have used a similarly designed crank hub assembly in many other motors prior to this and if there was that much crank wobble that they needed to add more support to the crank, we'd probably be seeing other issues. I think there are probably some tolerance and friction issues with the original parts of the assembly that BMW is replacing on an as-needed basis when they fail.

Definitely not trying to spark an online argument or debate here, but based on my prior knowledge and that gained specific to this issue over the past couple of days, I just want to make sure I shared my thoughts with others.

[S65V8]

The TPG crank hub can fix this

[lore2486]

Originally Posted by SROC5

The TPG crank hub can fix this

Lol certainly not the first version, maybe the new integrated design can.