IMS again

[maytag]

Originally Posted by piper6909

Subman makes some good points, but consider the cost vs benefits. You can get a good used 2.7 motor from $1500-3000 depending on location, miles, etc. An IMS will cost you around $1500. So you're looking, at best, at a 2:1 insurance policy against, at worst, a 15% chance the IMS bearing will actually fail.



Is it worth it?



I have a 2002 with 93K miles and Tiptronic. If I had a manual and needed to change the clutch, the IMS bearing may have been a "while you're in there" sort of thing. I don't, so it's not worth it for me.

FWIW, when I installed a used motor, 78k miles, into my '03 S, I elected NOT to replace the IMSB. There are so many things that can take out these motors, it seems the IMSB has a relatively low failure rate, comparatively. (When all is taken in aggregate)
Why bother?

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[BoxMann]

The cost/benefit analysis doesn't support replacing the IMSB. Not even close.

I can walk y'all through the numbers, but you probably know them already.

That said, if I were replacing the clutch, I'd probably do it then just as a "while you're in there" item. But not otherwise.

[piper6909]

Originally Posted by maytag

...There are so many things that can take out these motors, it seems the IMSB has a relatively low failure rate, comparatively. (When all is taken in aggregate) ...

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Agreed.

Originally Posted by BoxMann

... if I were replacing the clutch, I'd probably do it then just as a "while you're in there" item. But not otherwise.

Exactly.

[pilot4fn]

Originally Posted by BoxMann

That said, if I were replacing the clutch, I'd probably do it then just as a "while you're in there" item. But not otherwise.

Even bette point, thank you. Will follow the clutch and do both as the time comes

[mikefocke]

Of course there is always the chance that the new bearing is bad (low, perhaps, but always a chance) or the installation flawed.

There is accurate failure data from Porsche as revealed in the lawsuit. Only accurate as of the date of the lawsuit which is a long time ago and more cars have accumulated more miles since then. So are the failures higher now? One would think so as more cars are at greater mileage than was factored into the original admission by Porsche.

[BoxMann]

Originally Posted by mikefocke

There is accurate failure data from Porsche as revealed in the lawsuit. Only accurate as of the date of the lawsuit which is a long time ago and more cars have accumulated more miles since then. So are the failures higher now? One would think so as more cars are at greater mileage than was factored into the original admission by Porsche.

From everything I've read, failure rates for the Gen 2 bearing are anywhere between 5% - 20%. Pick your lucky number. IIRC, 8% was the number in the lawsuit, but that's on limited data that existed at that time, and therefore, should not be applied or relied upon universally.