If you own an S55 BMW F8X M3, M4 or M2 Competition model, you have probably read on the internet and various forums about the ‘Crank Hub issue’ which affects the S55 engine, on both stock and modified engines. Is this really an “issue” and does it need to be addressed in your vehicle? The answer is yes, we always recommend it.


Hundreds of these vehicles have come through our New Jersey shop through the years. Unfortunately, the crank hub in these vehicles is always a recommended precautionary modification. Why? Potential drivetrain failure, which can be $20,000 to replace – or at the very least, leave you stranded until the crank hub is replaced and the engine is retimed.

 Gintani Crank Hub Solution for BMW F8X S55 Engine



In these models, the crank gear is locked to the crankshaft with nothing more than a diamond sintered washer. This results in high friction, and a load of torque from the crank bolt to hold the timing in place. In certain circumstances, a high shock load from changing a gear, or harmonics over time loosening the crank bolt, the bolt moves and no longer holds the timing accurately. This may happen over time, or all at once, with every engine performing differently based upon a person's individual driving style. When the timing goes out by a set amount, it triggers a “Drivetrain Failure” on the dashboard which results in rough running, rough idle and reduced engine performance. 


When the timing goes out by a further amount, the ECU will actually prevent the engine from starting, because of the risk of damage. If it slips, the only course of action is replacement of the affected parts, as they are ‘one use’ only from BMW.


In most other vehicles, this is not an issue, as the crankshaft attached to the pistons turns the camshaft(s) attached to the valves, via a belt or chain. The gears are locked in place on the crankshaft and camshafts with a keyway, so that the relationship between the pistons and valves is always the same; i.e. there is no chance of the valves opening at the wrong time and hitting the pistons. This is known as the ‘timing’ of the engine.


Gintani Crank Hub Solution for BMW F8X S55 Engine 

The Gintani F80X Crank Hub Solution

The Gintani F80X Crank Hub is the only one piece crank hub on the market, providing insurance against the chance of the crank hub “slipping” or “spinning” and un-syncing the relative angles between the crankshaft and camshafts. If you are modifying your car, tracking your car, or even driving spiritedly, then upgrading your crank hub is highly recommended.


The Gintani F80X Crank Hub kit includes everything explicitly required to address the dangers of the factory crank hub: installation crank bolt, key hole drill bit and drill block, Gintani upgraded crank bolt and most importantly: Gintani F8X One Piece Crank Hub.


Gintani Crank Hub Solution for BMW F8X S55 Engine 


Located in the New Jersey area? We’ve made hundreds of these crank hub modifications and can complete yours as well. Learn more about our shop servicesreach out to our shop to set up an appointment or give us a call at (201) 666-3500.


Shopping online? Head over to our online BMW Shop, learn more about our G80 collection or other parts for BMW.


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