Original BMW Crankshaft Pulley Bolt M8x20 for BMW M2, M3, M4, X1, and X5 (2012–2021)

This Original BMW crankshaft pulley bolt fastens the harmonic balancer to the crankshaft hub on the BMW M2 CS and Competition, M3, M4, X1 xDrive28i, and X5 xDrive40e. BMW calls it an ASA-bolt and specifies it as an M8x20 bolt in strength grade 10.9, a high-tensile class used for fasteners that carry heavy clamping loads. Each bolt weighs 11 g (0.39 oz). BMW began producing this number in March 2011. It is made in Germany and sold individually, priced per bolt.

Original BMW Parts carry a 24-month parts warranty.

A harmonic balancer damps the twisting vibration the crankshaft produces with every firing pulse, and it also drives the accessory belt, so the bolts holding it work under steady load. BMW uses this same bolt on two very different engines. In the M2, M3, and M4 it mounts the balancer on the S55 six-cylinder, while the X1 xDrive28i and X5 xDrive40e use it on the N20 four-cylinder. Within the F82 family, BMW's parts data also applies it to the M4 GTS, M4 CS, and M4 GT4.

Technical Details

• Manufacturer: BMW
• Part number: 11-23-7-575-488
• BMW part name: ASA-bolt
• Thread size and strength grade: M8x20, 10.9
• Weight: 11 g (0.39 oz)
• Production start: March 2011
• Made in Germany
• Sold individually
• Warranty: 24-month Original BMW Parts warranty

Installation & Tuning Notes

These bolts are torque to yield and are intended for one-time use. Whenever the harmonic balancer comes off, fit new bolts rather than reusing the old ones.

Common Questions

Does the M3 use the same bolt as the X1 xDrive28i?
Yes. BMW uses this one part number on the S55 engine in the M2, M3, and M4 and on the N20 engine in the X1 xDrive28i and X5 xDrive40e.

Is this bolt limited to facelift cars?
No. BMW applies it to both pre-facelift and facelift F80 M3, F82 M4, and F83 M4 convertible models.

Fitment & Compatibility

Compare your production year and trim against the table below. With over 20 years of parts and fitment experience, PMB Performance can match this to your VIN.