The S55 crank hub failure has made its way to South Florida

[DBV]

UPDATE: official dealership diagnosis is a loose crankhub bolt. Apparently they've fixed it now and my car is ready to be picked up. Dropped off Wednesday early morning and now done end of the day Thursday. I can't imagine the damage was anything serious or their remedy extremely invasive. Once again, it occurred at low rpm so I'm sure that's a factor. I'm out of town at the moment and won't pick the car up until Sunday evening/Monday morning. I hope to talk to the tech then and will update the thread with my findings.

[CaryTheLabelGuy]

Originally Posted by minn19

No offense, but how are you so confident of this as fact. I'll concede you know far more about it than I do. But, this car and cars in general are rolling computers. It doesn't seem that hard to record a bunch of different parameters to see what is going on for various reasons. Especially max HP/TQ for this reason. Leaving out other special code to detect tunes or whatever else they want to look for.

How are you and others so sure what it can and can't record for data purposes? One of the reasons that the piggybacks are so popular these days, (besides simplicity etc.) is that DME's are so sophisticated and hard to crack now.

Show me an instance where warrantee work was denied due to a detected piggyback on the S55.

Also, a piggyback on the S55 isn't popular due to not being able to easily crack the DME, the piggybacks are popular due to the way the S55 DME actually works. Search my posts for more detailed information. Even Dinan is using a piggyback for the S55, because they understand how the S55 DME works in comparison to older, less sophisticated DMEs.

Last point, the DME can't physically read power levels, only a dynometer can do that (engine or chassis). Those kitschy little power gauges that BMW provides are simulated, not actual.

[CaryTheLabelGuy]

Originally Posted by DBV

UPDATE: official dealership diagnosis is a loose crankhub bolt. Apparently they've fixed it now and my car is ready to be picked up. Dropped off Wednesday early morning and now done end of the day Thursday. I can't imagine the damage was anything serious or their remedy extremely invasive. Once again, it occurred at low rpm so I'm sure that's a factor. I'm out of town at the moment and won't pick the car up until Sunday evening/Monday morning. I hope to talk to the tech then and will update the thread with my findings.

Thanks for the update! Glad to hear nothing catastrophic was damaged. I hope they replaced the whole assembly, however.

[CaryTheLabelGuy]

Originally Posted by MyFragileHalogen

I am not knowledgeable about how the car's computer works, but when I look at the kind of data the M-laptimer can pull out, I believe it isn't impossible for it to store speed, acceleration, GPS location, altitude and so on in addition to sensor readings to analyze what was going on with the car.

I could be wrong, but I believe the lap timer is using your phone for GPS data and acceleration computations. The S55 DME doesn't have accelerometers on-board, that I'm aware of. The DME does have a barometer, however as well as being able to read ambient air temps and IATs.

[minn19]

Originally Posted by CaryTheLabelGuy

Show me an instance where warrantee work was denied due to a detected piggyback on the S55.

Also, a piggyback on the S55 isn't popular due to not being able to easily crack the DME, the piggybacks are popular due to the way the S55 DME actually works. Search my posts for more detailed information. Even Dinan is using a piggyback for the S55, because they understand how the S55 DME works in comparison to older, less sophisticated DMEs.

Last point, the DME can't physically read power levels, only a dynometer can do that (engine or chassis). Those kitschy little power gauges that BMW provides are simulated, not actual.

Give me a break, I'm not in a position to know that information. It's the second time today you've used the classic unless you can prove me wrong, I'm right move.

You have your opinion and I have mine.

Again, how do you know this information is fact and are certain about what you are saying the DME can and can't do?

[MyFragileHalogen]

Originally Posted by CaryTheLabelGuy

I could be wrong, but I believe the lap timer is using your phone for GPS data and acceleration computations. The S55 DME doesn't have accelerometers on-board, that I'm aware of. The DME does have a barometer, however as well as being able to read ambient air temps and IATs.

Yes, it seems (not 100% sure) that m-laptimer relies on iphone for accelerometer and GPS. But the computer could pull out GPS coordinates from NAVI system right (even if the car doesn't have NAVI it has a built in GPS for the road side assistance and tracking)? Acceleration can be calculated from speed vs time. It's kind of fun to imagine what kind of info is stored and what they can find out from it if they are determined. Hope they don't store all the info permanently due to some size limit.

[M4 CSL]

Originally Posted by DBV

UPDATE: official dealership diagnosis is a loose crankhub bolt. Apparently they've fixed it now and my car is ready to be picked up. Dropped off Wednesday early morning and now done end of the day Thursday. I can't imagine the damage was anything serious or their remedy extremely invasive. Once again, it occurred at low rpm so I'm sure that's a factor. I'm out of town at the moment and won't pick the car up until Sunday evening/Monday morning. I hope to talk to the tech then and will update the thread with my findings.

Thats Great. They finally pulled my stock hub out. It looked 99.9% perfect. (Not damaged at all like the other guys one in his pic.)

At best there was a fine line around it. Pretty much all looked new. However we are replacing with brand new factory parts, and will loctite the bolt and use higher torque. There was no damage at all. But replacing all parts just to be safe.

[M4 CSL]

Originally Posted by Maltman

The look of a damaged hub

This is seriously damaged. Mine looked like new. Right Up the top of the fattest part, mine had a fine line, like the line on yours but finer. But the narrow end was perfect, where yours is all chewed.

[DBV]

Picked up my car today. Final word from the dealer is that the crunkhub bolt loosed, caused, threw the timing off, and ultimately caused the engine to stall. Luckily it was a low speed incident, otherwise I'd imagine there could have been significantly greater damage. The tech mentioned that it seemed as if there was an overrev, and that since it was low speed, indicated it may have even been a software glitch in the Rev Match feature. Regardless of the cause, they replaced the crank hub bolt and torqued it to spec after applying liberal amounts of Loc-Tite.

[CaryTheLabelGuy]

Originally Posted by DBV

Picked up my car today. Final word from the dealer is that the crunkhub bolt loosed, caused, threw the timing off, and ultimately caused the engine to stall. Luckily it was a low speed incident, otherwise I'd imagine there could have been significantly greater damage. The tech mentioned that it seemed as if there was an overrev, and that since it was low speed, indicated it may have even been a software glitch in the Rev Match feature. Regardless of the cause, they replaced the crank hub bolt and torqued it to spec after applying liberal amounts of Loc-Tite.

Interesting. I wonder if BMW is advising techs to apply Loc-Tite or if they decided to do that on their own. Do you mind asking them if this was advice directly from BMW?

[terahertz]

Originally Posted by CaryTheLabelGuy

Interesting. I wonder if BMW is advising techs to apply Loc-Tite or if they decided to do that on their own. Do you mind asking them if this was advice directly from BMW?

I agree. It would also be good to know what torque spec they are using to re-torque it.

[M4 CSL]

Originally Posted by CaryTheLabelGuy

Interesting. I wonder if BMW is advising techs to apply Loc-Tite or if they decided to do that on their own. Do you mind asking them if this was advice directly from BMW?

+1

Originally Posted by terahertz

I agree. It would also be good to know what torque spec they are using to re-torque it.

+1

Great questions. Stock torque was 100nm plus 270 Degrees.

[sA x sKy]

Just some advice for DCT users.. It might be a good idea to get the BMS kickdown blocker TYPE C (that's what Ando told me but don't have my car to verify) which may or may not prevent the hub from spinning.

Remember, the 4 times it happened to me was when I hit that kickdown and its happened to most DCT users this way too. The $10 investment for the kickdown blocker could be well worth it.

[JoeyBananas]

Originally Posted by sA x sKy

Just some advice for DCT users.. It might be a good idea to get the BMS kickdown blocker TYPE C (that's what Ando told me but don't have my car to verify) which may or may not prevent the hub from spinning.

Remember, the 4 times it happened to me was when I hit that kickdown and its happened to most DCT users this way too. The $10 investment for the kickdown blocker could be well worth it.

you know, I always assumed it was when you went WOT in manual mode and downshifted and it would select lower gear, I never even thought about when you are in automatic mode and you go WOT and it does it automatically being an issue....................


Kind of rediculous that you have to drive the car like this in hopes of not spinning the crank hub. It's easy not to use the kickdown in manual mode but seems like a hassle to have to think about it when in auto mode. (Hence the kickdown blocker I guess)

Quick question as I don't have the car. If you are in Automatic and you use the paddle to downshift, will the car downshift? Or no because it's in Automatic
mode?

Anyone know what Type for An M4?

http://www.burgertuning.com/downshift_blocker_BMW.html

[black335i]

C

[black335i]

BMW should just have a recall. Worrying
about flooring a M car. What a POS.I floor my 335
several times over the last 8 years with no crank bolt falling

[LAKERS333]

Originally Posted by black335i

BMW should just have a recall. Worrying
about flooring a M car. What a POS.I floor my 335
several times over the last 8 years with no crank bolt falling

Seriously, why do we have to worry about something like this especially if you tune the car and then have to worry BMW might not cover even if it wasn't related to the tune. Just terrible, I have avoided my kickdown feature pretty much completely and use paddles to downshift instead.

[Oliver Queen]

I'm starting to think BMW knows a solution but it might just be too expensive for them to recall all the cars than to let it happen and band-aid as it goes, ford pinto situation. I wouldn't be surprised

[DieGrüneHölle]

Seems like BMW always finds a way to fuck up every M3 engine. That is 3 in row with a major weak point.

[JoeFromPA]

Do you guys even hear yourselves?

We've had ~1 new crank bolt come loose in 2 months on this forum. We've got >40k S55s now out in the wild. So far several owners have even had very simple resets of timing and new crank bolts and gone home within a few days.

The S54 had a real issue when it came out. The S65 has been more rock solid though there is some fear of rod bearings. The S55 has not had any real issues emerge yet.

If this was a consistent, real issue we'd see:

1. Increasing numbers of failure
2. DCT users be able to create crank hub spin/timing issues with deliberate max RPM kickdown, or at least much more frequently create the issue

Instead we've got a slowwwwwwww trickle and several users who experience timing issues/first symptoms when driving down the road at normal speeds (Excluding Sameet).

This points more to an installation issue, a metallurgical issue, or a parts spec issue at some point during production rather than some chronic major engine issue.

[TomBMW]

So is this a relatively simple repair? From what I've been reading so far, no catastrophic engine failure? It's really sad to see an M car has these issues.

[DBV]

Originally Posted by TomBMW

So is this a relatively simple repair? From what I've been reading so far, no catastrophic engine failure? It's really sad to see an M car has these issues.

Mine took three whole days of diagnostics and actual repair labor, that's with waiting on parts to come in too. Pretty quick considering TPG says the replacement takes about 10-11 hours.