discussion S55 - Crank Hub

[ClassicB]

Hi All, a few of the S55's are doing some high mileages now and I have not heard of any 1st hand horror stories. From some basic research it seems to very sporadic and affects stock and modded vehicles. It seems less likely to go as opposed to rod bearing failure on the S65 or S54, but can also cause catastrophic damage.

The pro's and con's of getting it done or not getting it done, is the easy part (basically do you want to Risk it).

If you mod the vehicle, off course the more strain and more likely it is to fail, but my question, has anyone spun a Crank hub, or heard of a spun Crank hub in S.A?

Also this doesn't seem like a wear item, like rod bearings but an item that could be prone to failure due to a flaw in design. If it was a major item prone to fail, would BMW have considered a recall?

 

[Omar HS]

I have a friend who spun a crank hub a few years ago on his f80. His car was heavily modified with bigger turbos

 

[ClassicB]

I have a friend who spun a crank hub a few years ago on his f80. His car was heavily modified with bigger turbos

Thanks Bud!! I definitely think if you are modding, it's a must to get the one piece unit.

Do you know if he bent valves or got away with just replacing the crank hub and re-timing?

 

[Omar HS]

Im not sure

Will find out from him and let you know

I watched an interesting video on Kies Motorsports youtube channel explaining why its good to replace the crank hub and how its done. If you got a few minutes check it out

 

[Jaystol]

Keen to hear people's thoughts on this too.

My understanding is that it is really something to consider doing if you're modding. What's the costs involved in getting it done as a preventative measure?

I see kits available around the R12k mark. What does labour typically look like?

 

[Bonez0124]

I did some research a while back when contemplating modifying my M2C. It's more common in DCT variants and it is (un)luck of the draw, happening to both stock and modified S55's, I battled to find any real data where they were able definitively say what causes it. It's more for peace of mind if you are going to mod, in my mind unless you're going with major mods it shouldn't be an issue.

 

[KarshS]

I wouldnt risk it. If you have an s55 out of plan just get it done for piece of mind.
Just like knowing you need to do bearings on other M cars when you buy them.
Once off maintenance item.
last i checked this is a 30 to 40k job depending who does it. Labor intensive

 

[ClassicB]

I wouldnt risk it. If you have an s55 out of plan just get it done for piece of mind.
Just like knowing you need to do bearings on other M cars when you buy them.
Once off maintenance item.
last i checked this is a 30 to 40k job depending who does it. Labor intensive

I have been chatting to a few well known independants (not to name any names, but guys known for rod bearing jobs) and there is varying opinions on this, i was surprised. Probably because its not something thats as common as rod bearing failure.

On my e92 rod bearings was a no brainer.

For stock s55 cars, there is also a crank hub bolt capture kit, as an added precaution you can do for some peace of mind. I dont intend adding a tune so i have ordered one of these kits as a start and tackling some of the other s55 weak points.

Consensus seems that for stage 2+, you should be replacing the crank hub with the one piece solid unit but saying this you could always be one of the unlucky few on a stock car so you need keep this in mind.

 

[Jaystol]

I have been chatting to a few well known independants (not to name any names, but guys known for rod bearing jobs) and there is varying opinions on this, i was surprised. Probably because its not something thats as common as rod bearing failure.

On my e92 rod bearings was a no brainer.

For stock s55 cars, there is also a crank hub bolt capture kit, as an added precaution you can do for some peace of mind. I dont intend adding a tune so i have ordered one of these kits as a start and tackling some of the other s55 weak points.

Consensus seems that for stage 2+, you should be replacing the crank hub with the one piece solid unit but saying this you could always be one of the unlucky few on a stock car so you need keep this in mind.

Interesting. Please keep us posted.

Would the kit not involve essentially the same installation process and costs? Or is this a simpler process?

 

[ClassicB]

Interesting. Please keep us posted.

Would the kit not involve essentially the same installation process and costs? Or is this a simpler process?

Its made up to fit over the crank pulley, so very basic fitment, cost effective and not labour intensive. The idea behind it is to keep the crank bolt from backing up and remaining torqued (nothing is opened up). It would give you that extra peace of mind on a stock car and possibly stage 1, but anything more and the full crank job is no doubt the way to go.

Link:

BMW N55 S55 Crank Hub Bolt Capture - Vargas Turbo Technologies VTT-S55-CBC

BMW N55 S55 Crank Hub Bolt Capture - Vargas Turbo Technologies VTT-S55-CBC

www.fcpeuro.com

 

[kingr]

Its made up to fit over the crank pulley, so very basic fitment, cost effective and not labour intensive. The idea behind it is to keep the crank bolt from backing up and remaining torqued (nothing is opened up). It would give you that extra peace of mind on a stock car and possibly stage 1, but anything more and the full crank job is no doubt the way to go.

Link:

BMW N55 S55 Crank Hub Bolt Capture - Vargas Turbo Technologies VTT-S55-CBC

BMW N55 S55 Crank Hub Bolt Capture - Vargas Turbo Technologies VTT-S55-CBC

www.fcpeuro.com

this seems like a no-brainer solution to start with. cost-effective to prevent a disaster.

 

[KR_19]

Has anyone on the forum experienced a failed S55 crankhub, stock or modded?

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[jld010]

See you guys watch too many US YouTube content. Unless you doing stage 2 or 600hp numbers and driving like maniacal hooligans..downshifting and accelerating like F1 drivers.no need for the crankhub solution..it affects less than 1% of S55 engines. Gts tunes 368kw power outputs do not require the solution.

 

[whiteunderarm]

Has anyone on the forum experienced a failed S55 crankhub, stock or modded?

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I had the crankhub issue sorted before any issues arose on my previous F82…but I had a fully built motor running around 600whp…easy fix and imho worth the peace of mind.

 

[KR_19]

See you guys watch too many US YouTube content. Unless you doing stage 2 or 600hp numbers and driving like maniacal hooligans..downshifting and accelerating like F1 drivers.no need for the crankhub solution..it affects less than 1% of S55 engines. Gts tunes 368kw power outputs do not require the solution.

Thanks. Im trying to get as much insight as possible before doing any mods. I don't track or race the car, just the occasional spirited drive. I would like to improve the exhaust note so I was going to do the downpipes and exhaust. With that being done, I thought might as well do a stage 1 or 2 OTS map in time. Just trying to assess how big of a risk is it to the crankhub.

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[jld010]

Thanks. Im trying to get as much insight as possible before doing any mods. I don't track or race the car, just the occasional spirited drive. I would like to improve the exhaust note so I was going to do the downpipes and exhaust. With that being done, I thought might as well do a stage 1 or 2 OTS map in time. Just trying to assess how big of a risk is it to the crankhub.

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Phuckall risk then. Push the car and enjoy the S55..its a bullet proof engine..extremely reliable if driven the way you intend to.

 

[FiRi@Rennzport]

Thanks. Im trying to get as much insight as possible before doing any mods. I don't track or race the car, just the occasional spirited drive. I would like to improve the exhaust note so I was going to do the downpipes and exhaust. With that being done, I thought might as well do a stage 1 or 2 OTS map in time. Just trying to assess how big of a risk is it to the crankhub.

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I would suggest getting in touch with TMSS regarding DP and exhaust. Excellent tone from their setups

 

[KR_19]

I would suggest getting in touch with TMSS regarding DP and exhaust. Excellent tone from their setups

Thanks for the suggestion. Their work is topnotch, only issue is that I am based in CPT. However, I will get in touch with them when I am ready and see if there are any options that can be built up and shipped for fitment on this side.

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[Pisancho]

Thanks. Im trying to get as much insight as possible before doing any mods. I don't track or race the car, just the occasional spirited drive. I would like to improve the exhaust note so I was going to do the downpipes and exhaust. With that being done, I thought might as well do a stage 1 or 2 OTS map in time. Just trying to assess how big of a risk is it to the crankhub.

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Might be a small risk but keep in mind if anything goes wrong with the crankhub you will likely require an engine rebuild and last I checked thats a little over 100k. You pay to play as the saying goes. It is rare but happens often enough especially to tuned S55 motors. If going over the M4CS/GTS tune it is definitely worthwhile looking at having it done. Just keep in mind the GTS stock is 368kw to the crank, not wheels and lots of stage 2 M4s hit that figure to the wheels. A stage 1 tune on your car should be relatively fine.

 

[Sherwin@xcede]

If the hub spins, the engine does not fail. In fact it does more damage if it fails with the afternarket crank huv solutions. There's statistically very few cars that spin the crank hub.