So there's a 99' C2 that I considering and I know that they are more prone to catastrophic engine failure because of the rear main seal. I've got the records and the RMS was replaced at 20k mi (likely because of a leak, who knows how long it was leaking). It's been really well cared for and had the annual services/checkups since then, and at 45k mi there was no note of an oil leak. The next record that I have at 55k (not too long ago) the owner went in for his normal services and an oil leak. The shop made note at the bottom that the RMS is leaking.

So based on the above it seems that the RMS was likely leaking for less than 10k mi, the intensity of which is unknown. I'm going to get a blackstone oil analysis, but is that leaking RMS for a possible 10k mi enough to forget about the car all together? How much should I adjust my offer to compensate for replacing the RMS? It would be an advantageous trade deal for me, so I'm hoping that it's not that big of a deal if the oil analysis comes out good.

What would you do if you were me?

 

I have a 01 C2 that has had a weeping RMS for nearly 10,000 miles. I have not changed yet due to the clutch performance and wear are in good shape. I have been putting paper down to catch the drips. I will be putting the car in to get the RMS and intermediate shaft seal replaced and a new clutch next week though. I have not heard of the correlation between the RMS and Intermediate shaft failure. To replace the seal is approx $800-$900 the parts are around $10.00. I would have the seller replace if you can make the deal. Do a clutch while your in there $400 more. I would think that there are a lot of 996's out there with a weeping RMS and if the car is the one for you, make the deal and drive it like you stole it.
J. Greer

 

Yes, let's all get it straight...RMS leaks DO NOT cause engine failures. However, many "RMS" leaks are in fact IMS seal/bolt leaks. Without separating the bell housing, it really can't be determined where the leak is from, as the one sits directly over the other. So it IS important to address the RMS leak if only to verify that it isn't an IMS leaking and a pending catastrophe. If too much oil is leaking, then of course there are any number of issues from low oil pressure to an oiled and destrouyed clutch & flywheel. If I had any leak, that required work, and over 50k miles, I'd also do the clutch, RMS and updated IMS bolts all at the same time.

 

Yeah, if RMS leaking caused catastrophic engine failures there'd be VERY few 996's on the road out there.

 

Yeah. RMS = $900-$1200 repair, NOT catastrophic at all.

The 'catastrophic engine failure' is usually the intermediate shaft failure OR cylinder wall cracking. Both of these are essentially 'replace engine' repairs. There is no public hard data on failure rates, though both of these failure modes have been identified and discussed at length (do some searching). It certainly isn't 'likely', but it also isn't 'incredibly rare'.

 

To be candid, if a 1000 repair sends someone reeling, a P-car probably isn't for them.

 

An entire engine replacement isn't a $1000 repair, and that is what I'm worried about, not necessarily the RMS repair.

Thanks for all of your input. I did do some research a few weeks ago and remembered that the 99's were more prone to engine failure, and that I should check the RMS. I guess I just correlated the two directly.

If anyone has an idea off the top of their head, how much additional would it cost to replace the IMS seal and bolts at the same time? And you said clutch is ~$400 more?

 

I will be having the clutch, pressure plate, throwout bearing, RMS, ISS, all applicable bolts, pilot bearing, throwout lever bearing replaced next week for $1,300 by a local porsche indy who is highly regarded in the northeast. This is about $500 less than any of the local dealers in the Boston area. All the parts (less the clutch kit) add up to about $40.00 The list below is for the RMS and the bolts.
Good luck
Porsche 996 Rear Main Seal: PN# 999 113 490 41 (Or latest revision)
997-101-212-00 $9.41
Porsche Flywheel Torx Bolts PN# 999 073 092 09 (Quantity 8)
.71 all priced as each
Porsche Torx Case Bolts PN# 999 385 004 09 (Quantity 4)
.61
Porshe Torx Balance Shaft Cover Bolts PN# 900 385 275 09 (Quantity 3)
.24

 

If you're interested in increasing performance, you can have a lightweight flywheel installed when you do this too - will save some labor hours.

GMG (site sponser) has a very good one.