SSR Performance Double-Keyed 4-Pin Crank Hub - F87 M2, F80 M3, F82 M4 (S55)

Failed crank hubs have been reported throughout the S55 community, leading to valid worries about the integrity of the stock hub/bolt/sprocket assembly. A failed hub that has spun will cause the engine valve timing to skip or jump, potentially causing widespread engine damage. This new double-keyed and two-piece crank hub from SSR Performance has been well-documented to be a a great alternative upgrade over the stock design.

The SSR crank hub has two great benefits over the stock S55 hub:

Double-Keyed Locking Assembly - the valve timing chain sprocket and the oil pump chain sprocket are keyed together to prevent one from spinning independent of the other. The oil pump sprocket is also pinned to the crankshaft nose. Both sets of keys ensure the sprockets will not rotate out of position.

Two-Piece Design - the original assembly is three pieces (hub, engine timing sprocket, oil pump sprocket plus the bolt). The SSR design combines the hub and timing sprocket into one machined piece. This ensures that as long as the bolt is properly tightened to the crank the timing sprocket is always in sync with the crank. It's extra insurance to the double-locking keys mentioned above.

Installation of any crank hub solution is invasive to the engine. The oil pan must be removed so the subframe, steering, and suspension must also be removed or secured out of the way. The valve cover must be removed and BMW-specific tools to set the engine cam and valve timing are also required. Drilling holes into the crankshaft is also required for the locking pins to mate with the crankshaft. A drilling template and hardened drill bit are included. Links to suggested replacement parts are included below, such as bearing sets, gaskets, and hardware. Due to the immense scope of this project we can't list every possible replacement bolt, gasket, or component but contact us with any requests.

Tips:
1. This is the perfect time to replace your rod bearings. All of the work to remove the oil pan is the same and you don't want to do these jobs twice.
2. Engine oil and coolant will have to be drained so plan ahead to have fresh fluids on hand.
3. A lot of hardware on the S55 and the front subframe is 1-time use only and must be replaced when removed.
4. Any time the crankcase is opened up pressure in the oil system is released. You MUST prime the oil system when the work is completed and before starting the engine.

Includes:
New 1-piece crank hub/timing gear
New keyed oil pump gear
New crankshaft bolt
Drill bit and drilling guide/template