[JFP in PA]

Originally Posted by rexcramer

I have read multiple threads, visited several vendor sites and spoken to a local German car specialist (who has worked on my car) regarding the IMS bearing and possible failure. There seems to be several points that are echoed across the various ‘experts’ forums;

1. IMS failure is +/- 10%. (Unless it’s your and then it’s 100%) C’mon, fess up Porsche, what are the real numbers?
2. Lugging an engine is hard on the internals. I understand how torque/HP curves work and that makes sense.
3. Ergo, Boxsters that are driven hard are less prone to IMS failure. Or so suggest the ‘experts.’
4. Low mileage cars can somehow contribute to IMS failure. This seems like fuzzy logic.

In full ‘auto’ mode, my 97 (16K on the odo) really likes to shift low in the RPM range. Usually shifting under 2k, unless I put my foot in it. I can still be under 50MPH and it will shift up to 5th.

I usually only put it in ‘manual’ mode when I am in the twists’ or mountains and keep the revs above 3K.

So the question to my colleagues is do cars with ‘Tips’ have a higher IMS failure rate as the data would suggest?

I should probably just go for a drive and quit overthinking this.

Failure rates are a matter of probabilities, not transmission type. One of the most enduring comment is that running these engines for prolonged periods in certain RPM ranges seems to be involved, probably due to internal harmonics. Otherwise it is a simple probability calculation.