One of the most contentious subjects in the Porsche world is the intermediate shaft (IMS) bearing used in water-cooled 911s and Boxsters and Caymans from model years 1997 to 2008. So when our test drive and inspection videos of a 986 Boxster and 996 Carrera collectively achieved nearly 50,000 views, the PCA decided to follow up with an in-depth series to dispel myths surrounding the problematic IMS bearing these Porsches were equipped with from the factory. The first video explains what an IMS assembly is, where it resides in the engine, and how it changed through the years:
Last year we (the PCA) took a trip out to Flat 6 Innovations research and development facility in Georgia to learn all about the intermediate shaft (IMS) and the IMS bearing in Porsche’s first water-cooled flat sixes. These two engine components have proven problematic in some Porsche 911s, Boxsters, and Caymans from model years 1997 through 2008. In this video, we explain the four stages of IMS bearing failure:
In our last video, we covered the general subject of what the intermediate shaft (IMS) and the IMS bearing are and the functions they serve in Porsche’s first water-cooled flat-six engines from 1997-2008. In our second video, we show you ways you can reduce the wear of an original IMS bearing in the chance that you still have on in your 911 or Boxster.
In our last video, we covered the general subject of what the intermediate shaft (IMS) and the IMS bearing are and the functions they serve in Porsche’s first water-cooled flat-six engines. In this second video, we show you ways you can reduce the wear of an original-style IMS bearing in the chance that you still have one in your 1997-2008 911 or Boxster.
Keep in mind that any mechanical part will fail with use over time, and the IMS bearing is no different — even if you take extra care of it. However, if you’re in a situation where you cannot or do not want to replace your original-style IMS bearing, watch the video above for some tips on how to reduce bearing wear and extend its life:
We’ve covered a lot of ground regarding what an intermediate shaft and IMS bearing are, how to extend the life of your original IMS bearing, and the bearing’s four stages of failure. In the fourth and final video of this series, we explain the different types of IMS bearing retrofit kits available on the aftermarket:
For more videos on the Porsche IMS Bearing issue, we recommend checking out Jake Raby’s Rennvision Focus On: IMS Bearing Failure series. Jake Raby is the founder of Flat 6 Innovations and the co-developer of the IMS Retrofit and IMS Solution intermediate shaft bearings for Porsche M96 and M97 engines:

In this video series, Focus On: IMS Bearing Failure, Flat 6 Innovation’s Jake Raby discussed the Porsche intermediate shaft bearing problem on 1997-2008 Porsche Boxster, Cayman, and 911 models.