[Porsche Boy]

Best analysis of the IMS problem I have found which might account for why they fail early or after many miles:

IMS thoughts from Mikes Specialty Automotive:

Ironically, although my background is in a different industry, I had 35 years' experience with the same precision bearing that Porsche uses in their cars. I found the failure rate to be very similar both in my former industry as it is in Porche's.

Three things caused the bearings to fail:

1. Bad installation during the manufacturing of the product. I have a feeling that engines that were built outside of Germany are sub-standard. Bearings that might have been damaged during installation would have accounted for the early engine failures of 10,000 miles.

2. Breakdown of the seals that lead to contamination of the lifetime grease. At this point, it only a matter of time before you have chunks of your IMS bearing swimming in the oil.

3. Over-stress of the bearing wherein an over-rev from a bad downshift causes huge stress on all engine components of your Porsche. Automatics don't have miss-shifts, and I think that this is why you see less IMS failures in this type of car.

What to do to protect your Porsche Boxster:
In my case, I will change the bearing on my Porsche Boxster every 40,000 miles with a new Intermediate Shaft Bearing (IMS). This is not crazy, because it is a high end sports car. Ferrari's of the same year have their timing belts changed every 30,000 miles at a cost of about $12,000.00.