The TRUTH about BMW S55 Crank Hub Failures & Fixes!

[@Enron98]

The M4 GTS is a tuned S55 at 493 horsepower straight from factory. It has the same crank hub as the base M4 and less than 1% of them have this crank hub issue. If I decide to run a more aggressive tune than that, then I would probably change it. But on stock applications/stage one tunes probably won’t. I am skeptical of companies posting in BMW forums magnifying the problem to sell their product. Just my opinion.

[@BTSyaya]

I bet less than 1% of f8x cars stay stock. Clearly you must not be familiar with what bimmerworld did to their m4

[@hovnojede010101]

@@BTSyaya your perspective is skewed by your location, forums and facebook groups. They've made 100k F8x M3/M4, 99 percent are definitely not tuned lol.

[@hovnojede010101]

Forums, especially in the US, are great for blowing "problems" out of proportion. If a 450hp engine was made to last 100k miles, don't be surprised if your 700whp "FBO JB4 BM3 meth build d00d" lasts 40k miles only.

[@mcintosh.motors]

On my F80, after 3 years of ownership (2nd owner) the car hasn’t seen anything past factory HP ranges in it@: life. It’s tuned via a CS map currently and at 100K currently with no sign of stopping soon.

[@MT-xy7fw]

I agree, they make big money to sell the parts and labour.

[@ohtwo23]

I was turned off of adding CBC after pics started surfacing on the forums showing them rusted ass bolts even on the “better” branded ones. My 17 f80 comp is stock other than csf chargecooler with 92k miles. All is well so far and I beat on mine often. Misha (nurburgring guy) says the ring has 2 s55 ring taxi cars both with over 150k track miles and both are still running the stock hub. If you’re not tuned past stage 1 you are fine on stock!

[@OlehVasiutynskyi]

This guy is great with explanation and emotions effort that he put in this short video! Great content, definitely really useful if you are on the market for such kind of solution for crank hub issue.

[@Respect_N55]

Thank you for finally addressing it! Went ahead with the VTT splined Crankhub V2 and the CBC, and running 500+ ft lbs torque all good! More of a safety in my case than a necessity 👍

[@Tex777_]

My concern with the pins and keyways would still be shearing (think S54 VANOS oil pump). With 4 relatively small pins, that's still a lot of torque that could be applied if / when the crank bolt backs out. Thoughts?

[@BimmerWorldMedia]

Those pins are certainly not meant to take the load of the spinning crank, so if the bolt backs out all bets are off. That goes for any crank hub. So thats why we recommend other safety measures to keep that from happening. If the bolt backs out on any hub, bad things are going to happen.

[@arturskristgolds8829]

Hello !! If i got 40k miles do i need do this ? i got stage 1 ? so many people saying i need do 100 proc but others said 2 stage need then .. can you tell me how it should be ?

[@ccxcv23]

I'd like to get your professional opinion, I have a completely stock 2020 f82 about 25k miles. The only thing I plan on doing to it is adding a AA Single Mid pipe for the crisp sound and that's it. Not going to tune it (first M car) and it's already scary powerful imo. What is your recommendation? Leave the crankhub alone or get the Vargas Spline Lock? I'm asking because I thought about doing the 4 pin SSR just for the peace of mind entirely.

[@BimmerWorldMedia]

Is the car a 6spd manual or DCT? If the car is going to live as a street car and not see track time I would say you would be fine keeping the stock hub in place. If its a manual I would lean even more towards keeping it stock. If DCT and going to the track I would consider it, but still not necessary. If you are willing to do the work for peace of mind, then thats certainly not a bad thing, but I wouldn't put the car you described in the "danger zone" of needing the crank hub addressed.

[@MILESPH71]

Ok I need professional opinions. Have a 17 f82 got it at 13k mileage. Ran it from 20k to 30K on stock hub with BOotmod stage 2h tune. Had to replace the hub not because it slipped but because the capture plate that was put on actually had failed bolts which made the harmonic balancer rip off. Reason the hub was taken out was to extract the bolts. Do I go for the keyed crank or not, I track the car a lot and didn’t have issue but now i am nervous.

[@Itschaboylamari]

Honestly I've been looking around and see the ssr is kinda the main solution if want abuse the car and not worry

[@ericvermeulen9853]

Good and proper, no BS marketing, thanks

[@JohnnyLehti]

I disagree on that it has with horsepower and torque to do. I say that it is purely very fast rev changes that creates transmission chocks that is the cause. 450 or 700 hp doesn't matter. The reason to why it happens more frequently on the S55 engines is something that noone mention. Oil pump drive chain. The S55 has significantly more resistance on the hub than a N54/55 because of the regular oil pump AND the scavenge pump for the return lines from the turbos. This creates more resistance on the hub when the rev changes are extremely high which makes the hub more prone to slip. It is much worse for the hub to upgrade the software for the clutch on the DCT gearbox or put in a race clutch on the manuals then increasing power as i see it.

[@darylmorse]

I have heard a few people claim the S55 is not an interference engine, so if the crank hub spins, there will not be valve / piston contact. I find this hard to believe, because I've heard of valve / piston contact with a spun crank hub, but I think there was also a money shift involved. Can anyone confirm the S55 is or is not an interference engine?

[@franklinwatson7767]

Own a '15 F82, been running 600 wheel HP for over 5 years now on the stock crank hub. The issue is blown way out of proportion IMO, but great marketing though!

[@BimmerWorldMedia]

As with everything, everyone's results may vary. Lots of variables, but we are just giving out information and providing solutions for those who feel like they'd like to cover this possible failure. Trust us, we love hearing about happy BMW owners that AREN'T experiencing problems :)

[@FreeYSLM2]

My grandma smoked cigarettes for 50 years & never developed lung cancer. Doesn’t mean smoking doesn’t cause cancer

[@franklinwatson7767]

Mixing apples and spark plugs buddy. Despite a car, just like a human body needing fuel to run, a human body is no car. A buddy of mine was a tri-athlete, best shape, strict diet, no alcohol, drugs or tobacco, and died of cancer at 38 years of age. Were talking engine and horsepower here B.

[@nathanscreene4818]

Mines exactly the same dare I say it, 600 on stock hub 2 years in fingers crossed 🤞🏼

[@franklinwatson7767]

@@nathanscreene4818 You'll be good to go, but I recommend upgrading the hub if you ever decide to upgrade the turbo's.

[@Elledollar]

Is it a good practice to also change the rod bearings if we install the crank hub upgrade ? I mean its not every day we open the engine...

[@aragrox]

How is the piece built, cnc or forged, cast? How many people here check the torque spec when it happened before removing the bolt?

[@JiuJitsuM4]

The Vargas VTT2 spline lock worked great on my 730 WHP F83. Currently running the SSR crank hub for my F82. They both work great. SSR is bulletproof.

[@elias1208]

Would love to know the difference in driving dynamics that you felt between F83 and F82. I have the F83 but im curious if F82 is that big of a difference

[@jonathankrum3016]

Great video and info! Looking at the VTT solution on an m235i running a speedtech top mount.

[@user-ki8zf1rp1e]

How accurate does the drilling have to be between the 4pin and 2pin crank hub fixes? I've heard a couple stories about people drilling for the 4pin but later having the studs break off in aggressive driving conditions due to the screws being slightly misaligned. Would the 2pin allow for leeway or are they both a delicate matter?

[@BimmerWorldMedia]

Drilling into your crank should absolutely be done with precision. It's certainly a scary job for those that may not have experience in doing something at this level. Not saying its impossible to do in your own garage, but you really don't want to mess up the alignment of drilling holes into your crank, period.

[@IwokeUpInSOMA]

Really enjoyed the video. You know your stuff.

[@xxiixx8766]

So even if it slips, it can be a easy fix? i have now 500hp f87 but im just scared to drive it hard now.

[@colinfitzpatrick9931]

It can be just a retime of the motor if there's no valve contact. Worst case scenario you're rebuilding or replacing the motor

[@davechats5355]

Excellent video. Best explanation of this system that I have seen. Really wish I knew about this before our stock M2 Comp jumped timing due to a missed shift but seeing this design it’s not at all surprising. Going with the SSR 4 pin while it’s apart being re-timed. A friction fit timing sprocket BMW? Really? Too cheap to put in a $5 key??

[@snikwadRR]

If the issue is te crqnk hub bokt eventually loosens, the. If one can find a way to secure that bad Jackson so it doesnt slowly start backing out for any reason, like the vargas capture plate. Why wouodnt that be a sufficient fix?

[@S54VR6]

because they can't make as much money scarring people into buying this overblown part. shops do the same thing because its 3k+ job. only reason to actually worry is if you a tracking a tuned car and abusing the shit out of it.

[@RAElias]

Any thoughts on other brand solutions, particularly Gintani, which I believe is a true single piece.

[@BimmerWorldMedia]

These are the only ones we have first hand experience with - try not to pass judgement on parts we haven't really installed and tested ourselves.

[@intercede007]

Thank you so much. I'm buying an F8X car next year for a street and occasional track toy, and the crank hub issue is a nagging problem in the back of my mind. If I'm test driving and inspecting a used car, is there any way to tell whether the car is having the issue without a code reader? Would the CEL be triggered relatively quickly?

[@BimmerWorldMedia]

If its jumped time from a spun hub it will trigger a CEL fairly instantly. You will know.

[@e46silverbullet62]

have there been any reported failures with either the Pinned hub (any # of pins) or the Splined hub?

[@BimmerWorldMedia]

Not that we are aware of unless it was installation error or some other catastrophic engine failure that took out the hub as well.

[@sebastiankulesza3782]

GREAT CONTENT !!! THANK YOU!!!

[@timlad123456]

Less than one percent of the vehicles produced report the crank hub spinning only in extreme power modifications does this problem occur. If you tune your bmw get the crank hub modification.

[@davechats5355]

2021 M2 Comp. Bone stock. 405hp. My wife missed a shift (manual gearbox) and that POS hub slipped and jumped timing. Now that I see the design I realize what garbage it is. You need a keyed sprocket! Not a friction fit.

[@timlad123456]

@@davechats5355 So sorry that happened to your whip that is a beautiful car, missing a shift in any manual can be disaster and I agree with you it is a poor design for a motor with over 400 hp

[@mazpr2025]

​​@@davechats5355 exactly, or even at least have the faces to be teethed/keyed like Audi does with their dampers against the crank face, never ever flat one against the other.

[@MW-uy3np]

Did GTMore have the crank hub repaired?

[@BimmerWorldMedia]

The GTMore has the SSR Double-Keyed 4-pin hub installed.

[@Birdhouseboi810]

Is there a crank bolt lock for m50 engines?

[@BimmerWorldMedia]

Nope. It's certainly not good to have any crank bolt back out, but at least for the M50 it doesn't instantly destroy your engine's timing. Not really an issue that needs to be addressed.

[@Birdhouseboi810]

@@BimmerWorldMedia Very true. I've only ran into the issue of the keyway sheering off on luckily just the crank damper. Ignition and fuel timing was off but luckily the mechanical timing was okay. Some back story, it is an M50 stroker with the M54 3.0L rotating assembly

[@BimmerWorldMedia]

@@Birdhouseboi810 Yup completely different design where the crank bolt has nothing to do with keeping the engine in time, just keeping the crank pulley on the engine. You can chuck that bolt and you'll certainly have a whole different list of problems, but losing engine time isn't one of them!

[@NURSEBOBBY]

I think you are definitely RIGHT because... I am almost always wrong

[@beastofackworth]

You always hear about crank hubs thay soin but dint hear aboit the 10000 that dont. I agree with the initial statement that DCT cars with bug kick down events cause the main problems. I drive everywhere in manual mode so this isnt a problme. My car is standard because a car that does 0-1000 in 4 seconds is quick enough on the road.

[@telbor3378]

I wonder if the N57 engines use the same crank hub. I drive an f36 with the N57D30 so a diesel engine which while not even being the most powerfull engine of this generation delivers more torque than the M4 Competition

[@BimmerWorldMedia]

Nope, it appears the N57 diesel has the timing gears built into the crank, not the same design so no fear in failure there.

[@ps2cho]

If someone is keeping the S55 completely stock, has there been any incidents of this spinning? I.e. is there anything a stock owner needs to worry about whatsoever?

[@yg78t76t7]

Yes

[@azizazoz88]

Mine had spun with stock f87

[@user-jl7hx1zz6d]

Do you guys do installs for customers?

[@BimmerWorldMedia]

The yellow F80 behind Phil is a customer's that we just performed a hub upgrade on. Shoot us a call if you are interested.

[@user-jl7hx1zz6d]

@@BimmerWorldMedia Very good to know. Thanks 😊

[@yg78t76t7]

I am on a Stage 2 map in a 112k BMW M4. Granted, I may be one of the lucky ones, but haven't had any issues yet for at least 20k miles since the car has been tuned. Now just because I haven't had an issue, doesn't mean you will. If you have the money, GET IT DONE.

[@stevehale2315]

My Stage 1 carbahn s55 spun the crank hun within 250 miles of being tuned. It definitely happens folks. 24,000 miles on the clock.

[@AaronEmerald]

How bad was the damage

[@borderwave2]

Why would a higher power level be associated with more crank hub failures? The parasitic load from the cams and oil pumps should be the same on stock and tuned cars, assuming they have the same rev limit. "More power = bad" doesn't offer a logical explanation for the failure.

[@BimmerWorldMedia]

More power/torque changes the rate of acceleration/deceleration of the engine's rotating assembly dramatically. We aren't worried about parasitic load, its not the accessories and valvetrain putting the stress on the timing chain, its the crankshaft's ability to transfer enough torque to simply spin the hub assembly. More power = bad is a very simplistic way of saying it, but IS the logical explanation to this failure actually. Much like exceeding the clamping force of a clutch due to too much torque, this is a similar concept at the front of the engine - but the friction washer is the "clutch" in this scenario.

[@borderwave2]

Thank you for providing that response. I appreciate it!@@BimmerWorldMedia

[@deruniversalindikator]

But why didn't BMW do this as standard, why would you do two pieces, which should stay together and not just one big?

[@jldp24]

How do ppl think the crank hub is an issue..it is widely regarded as a myth

[@markwhite6719]

Hey man nice video where are you located and do you do the crankhub fix and contact info please

[@BimmerWorldMedia]

We are located in Dublin, Va and we do take in some customer work as schedule allows. Feel free to reach out to us via our website if you'd like - www.bimmerworld.com

[@SteveBennet500]

5:35 template + hand drill = 0.001" drilling accuracy? lolol noooo this is still a hack job imo

[@andrewchiles]

Agree. lol there’s no way that anybody doing these pinned designs is even close to accurate enough to not put stress on the pins.

[@nathobean8582]

The problem I have with these videos is it’s too much opinion and not enough facts/evidence. Admittedly it’s difficult with the limited dataset, but people need to be more careful with these blanket statements. To state pinning the hub is the ‘be all, end all’ is misleading when there have been numerous cases of the pins snapping. The fact people think applying huge amounts of torque to a few tiny pins vs. a friction disc is magically better concerns me. Not to mention if the pin holes are drilled even the slightest bit out of line, it increases the chances of snapping the pins. Then, to state the Vargas solution is good for lower-end applications, suggests it’s unsuitable for higher-end, which is also misleading. There’s no evidence of the VTT hub failing, except during V1 when they had some QA issues with the hardness of the metal used for some batches (unrelated to design). Engineering science concluded long ago that splines transfer torque more effectively than pins. It’s why transmissions, differentials etc. are designed the way they are. But, the VTT not fixing the oil sprocket is a problem. Yes, the load is less, but, I’ve seen first-hand the oil sprocket spin which caused the engine to lose oil and end up completely fried. An engine with no oil flowing through it won’t last long. I understand why VTT designed it this way, as it’s cheaper to install etc. but I only wish they made a one-piece design also. There is no ‘perfect’ solution, other than the S58 unfortunately (no separate hub). The best solution would be a 1-piece spline lock, but no one has developed one.

[@chrish5503]

The TRUTH is that this basically never happens, and it's another E92 M3 Rod Bearings cry-wolf. Many years in the forums, and and olnly heard of this theoretically; I know NO ONE that this has happened to.

[@周斌佶]

why BMW did awear this simpple problem when develop the engine?? The engineer there not smart as the aftermarket people???

[@yg78t76t7]

Because BMW engineers do not expect everyone to mod their car to 600-700HP

[@davechats5355]

They did it so their dealerships can charge between $6000 for retiming the engine if no valves get bent, or sell the customer a &35,000 engine if the valves do get bent. Dealerships make their money on the service department, not sales

[@anthonyt4981]

before anyone starts ridiculing bmw for this design, they claimed it acts like a fuse. We all know what fuses do, they maintain a system when operating within spec. If the system goes out of spec, the fuse blows to protect the components. When the sprocket spins, your pistons and valves do not make contact. The s55 in its factory form is meant to produce at max m4 GTS power. Pumping more power out of a s55 requires a bigger fuse.

[@BimmerWorldMedia]

Absolutely correct. BMW, as always, knew exactly what they were doing. You push their design well beyond the limits they planned for and of course you're looking at a possible failure - that IS the design. Thankfully for us, the aftermarket was ready to provide a solution that may not agree with the max power level intended by BMW engineers :)

[@cptclutch2530]

I thought the spinning is what can cause contact if you are unlucky?

[@BimmerWorldMedia]

@@cptclutch2530 That is correct, a large enough slip can create piston to valve contact. I didn't catch that in his comment, it WILL cause internal engine damage. This is why its important to catch before it happens. A small slip can cause codes, a big slip (more likely if pushing big power) causes a new motor.

[@chris5401000]

More realistically this is a fuse that either saves the component or detonates the component. It's more of a dice roll.

[@anthonyt4981]

@@BimmerWorldMedia i stand corrected.

[@terrancecollins2696]

The friction washer design IMO was someone SEVERELY overthinking at BMW