Lower Main Bearing Shell, Brown, BMW - F87 M2 N55, F8X M2/M3/M4 S55

This part is listed by BMW as BMW part number 11217849239 (11 21 7 849 239) and is described as a lower main bearing shell for the S55 engine used in F87 M2 Competition, F80 M3, and F82 M4. It's also used in the N55HP engine in F87 M2. This is an lower shell, with a brown color code (crank ID 5), and is the standard 56.00mm size.

Important Bearing ID Note: BMW has a different way of identifying S55 main and rod bearings. Locate a letter code on the passenger side of the engine block and combine that with a number on the front of the crankshaft. The letter corresponds to the upper bearing shell: D = blue, E = brown, F = purple. The number corresponds to the lower bearing shell: 4 = blue, 5 = brown, 6 = purple. Example "D5" would be a blue upper and a brown lower shell. It would not be unusual to have a mix of codes and colors. Note that bearing position 4 is the upper thrust bearing shell and is a different part number than the rest. The oil clearance is 0.020-0.046mm (0.0007-0.0018") for each crank journal (but BMW does not tell you which color is the thinnest-thickest). Start with the bearing codes from your engine and contact us if any of your journals have a too-large gap.

This is a Genuine BMW S55 main bearing shell with a two year warranty. Buying a Genuine part will usually be more expensive than an OEM or aftermarket brand but you are assured that it meets BMW's designs for fitment, performance, and longevity. It will also be the very latest design, incorporating any updates or revisions that an aftermarket brand typically will ignore.

For full BMW fitment information or for assistance from one of our BMW experts, we recommend calling us at 877-639-9648.

BMW Fitments:

2 Series
F87 (2016+) > M2 CS Racing
F87 (2016+) > M2 Competition S55 (2019+)
F87 (2016+) > M2 N55 (2016-2018)
3 Series
F80 (2015-2018) > M3 (2015-2018)
4 Series
F82 / F83 (2015-2020) > M4 (2015-2020)
F82 / F83 (2015-2020) > M4 GT4
F82 / F83 (2015-2020) > M4 GTS
X4 Series
F26 X4 (2015-2018) > X4 M40i xDrive