AC Belt: what is correct part number?

[JonM]

EPC lists 2 part numbers for the AC belt and they are 1" different in length. One is 11287841529 and the other is 11287841529. Which is correct?

EPC: http://www.realoem.com/bmw/enUS/show...20#11287838200

[deansbimmer]

It has to do with your production date. Some of the earliest 2008 M3's have power steering pumps that rotate in an opposite direction than later builds. The early style PS belt is slightly smaller and runs over the top of the PS pulley and is ribbed only on one side. Later builds the belt is slightly larger and runs under the pulley- this belt is ribbed on both sides.

Early style: If your AC belt goes over the PS pulley use belt 11287838200.

Late style: If your AC belt goes under the PS pullet use belt 11287841529.

[JonM]

deansbimmer, EXCELLENT info, many thanks. Would have been easier if EPC listed the cutoff dates. My 5/08 build is the later double-ribbed style.

[deansbimmer]

Originally Posted by JonM

deansbimmer, EXCELLENT info, many thanks. Would have been easier if EPC listed the cutoff dates. My 5/08 build is the later double-ribbed style.

They do list cutoff dates in a way. You'll notice the "start date" on the later style belt is 04/29/2008 which corresponds perfectly with your MFG date.

In my experience they don't list "stop" dates for superseded parts unless the part is no longer manufactured or available which isn't the case with this part.