Sorry, but they don't know what they're talking sbout. Send a message to Flat 6 and ask them how many early 05 3.8 motors they've changed the IMS bearing in. I know Para82 (Nick) has had it done in his 05 Launch Edition 997... in fact I bet most of the launch cars have been upgraded. Do a search on launch cars and IMS because being a launch edition means it was built at the beginning of the run. The C2S launch edition cars are all black on black, 3.8L S cars with PCCBs, adaptive seats, sport chrono, and full leather.

For 3.8L motors, up to engine number M97/01 68509790 has the smaller IMS bearing and csn be upgraded without splitting the case whereas Engine number from M97/01 68509791 has the larger revised IMS and can't.

 

The only way to really know if you can or can't is to pull the engine or transmission (for example, at clutch replacement time) and inspect the IMS flange. If it has the small retaining nut, it's the easily replaced style. If the large retaining nut, then it's "split the case to replace". For the split-the-case-style, you could remove the seal on the sealed bearing to try to encourage fresh lubricant reaching the bearing innards.

 

Thanks, have sent him a PM

 

Or, you can just leave it as-is. The failure rate for this bearing is extremely low.

 

 

IMS failure at 50,700 miles, 2005 997 build date 06/04.
I am a tech at a German repair shop, customer came in with a complaint of a loud engine noise while pulling into his driveway. He shut the car off immediately, and had it towed to us. I pushed the vehicle in and pulled the oil filter. Engine oil and filter were full of metal, we recommended a full engine rebuild. Car was towed to another shop where the trans and ims were pulled for a second opnion... ims was completely destroyed with damage to the ims shaft. I purchased the car from the owner pulled the engine from the car and sent it to vision motorsports for a full rebuild. I am the 3rd owner of the car, second owner purchased it at 6k miles. This is the second IMS failure I have seen, both were low mileage, light around town driving. I have installed a few different styles of ims bearings and retrofits with no problems so far. The very early build date matched with a lot of low rpm mileage is what killed this car...

 

2008 997 C4S, 133,764 miles, NO FAIL

 

 

I got my car at 16k and am about to turn 20k 6 months later with no issues. However, I have the 2006 C2S, so I wonder how relevant my input is since the failure rate for 2006 and older 3.8 motors seems to be statistically insignificant.

 

I believe there have been a couple but only on tracked cars where continuous high RPM usage has the bearing surface speed exceed the design parameters. Mid 05 and newer with the larger bearing, not much to worry about with proper maintenance and treatment.

 

It is indeed.

 

Too bad I already voted no.

Failure at 102,500. 2005 c2 manual.

 

I'm really sorry to hear of your misfortune. Will you be rebuilding or selling the car as a roller. OEM small IMS bearing I presume?

Although it's very unfortunate for you, it's a good example to others who believe that the small bearing motors, if they make it to or past a certain mileage, will remain fine - they won't ! Any motor with a small IMS bearing that is replaceable, should be replaced. Consider it a $2,000 insurance policy to prevent a $20,000 repair.

 

Another problem in this thread is that someone in their infinite wisdom decided to combine both the 997.1 and 997.2 figures severely diluting the number of 997.1 failures making this poll extremely inaccurate and misleading since the 997.2 does not have IMS failures. IMO, they should either remove the poll results all together or separate them back so it is misleading.

 

It probably goes beyond 997.1 and 997.2. I more likely goes to the specific serial number of the engine to determine which bearing was used.