Ben_C

Hi all,

I am looking at a 2003 C4S with 25k miles. The RMS and intermediate shaft housing were replaced under warrantly due to a leak. What does this mean for the intermediate shaft bearing? Would it have been replaced? Is this a sign of potential further issues with the IMSB?

Thanks, Ben

logray

If the IMS flange cover was replaced then it's about a 0 in a million chance the dealer would have replaced the bearing as well. The dealers only replace IMS flange covers, seals, and bolts under warranty work. The only chance would have been if the customer asked for the bearing to be retrofitted and they agreed to do it (some Porsche dealers will not retrofit). The new seal and flange cover or replacement will help prevent external oil leaks, but does nothing for the longevity of the bearing itself.

As for a sign of potential further issues? The jury is hung on this one. Some are in denial whereas others say that every car is a ticking time bomb. Of course those are extremes... the "official" word is that as much as 10% of all cars may experience an IMS bearing failure at some point in 90,000 miles. More than you ever want to know about the IMS bearing subject can be read here:

http://www.lnengineering.com/ims.html

But basically if you have any concern in your mind and you buy into it, then have the bearing replaced and negotiate it as a part of the asking price ($1500 to do an IMSB retrofit at most shops).

You can also negotiate the price of the car based upon the need/desire to install the IMS guardian.

Ben_C

Thanks logray,
I have been reading about the IMSB here (and been following your engine rebuild - is it driving yet?). At the end of the day any engine is a time bomb for one reason or another - these ones just cost a bit more to fix! I am not sure about guardian vs bearing replacement given that at 25k miles the clutch should have a lot of life left and RMS is alrady done. This probably would steer me to a Guardian and the IMSB when I get to it or when an issue develops.

Cheers, Ben

dotframe

For what its worth I bought my car with 30k miles and decided to not even worry about these issues until my clutch was due for replacement. Drove the car less than 10k miles and the clutch went so I took care of it then.

soverystout

My car had the RMS replaced and the IMS flange cover replaced.

The upgraded cover has a triple seal that will most likely prevent the opening from leaking oil.

That doesn't help things. If someone on this forum spots a leak in the area between the engine and trans, they think, "could be RMS, could be IMS but either way, I need to address it".

With a better seal on the new flange, you have all the oil that is in the IMS tube stuck in there, which has most likely/probably/maybe overcome the IMS bearing seals and washed out the permanent lube.

That is why LN says that if you are not going to change the bearing, at least chnage the oil (a high quality synthetic) every 6 months or 5K miles.