" Ant " does a loose version of explaining the IMS bearing issue and replacement.
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Great video. Looks like a piece of cake. 
Stan Galat posted:Great video. Looks like a piece of cake.
So it appears but I think that would be one time I would write a check ..oh and add $1,000 for a 996 clutch set.
I stopped by Rich MacKoul’s the other day to check on him - Remember that he owns the original 1955 Pre-A Speedster I used for dimensions from his dashboard. He lost his wife last Fall to Dementia, so I stop in from time to time to pester him (what are friends for?). For those concerned, he’s doing as well as expected, day to day.
He’s about to do the IMS upgrade on his DD, a pretty, blue on blue 996 convertible and asked which kit my son used on his. Turns out there are two kits, one that replaces the original IMS bearing with another sealed unit, and at least two other kits that do the oil-fed bushing, one from L&N Engineering as well others.
The oil-fed conversion is a much bigger deal, hogging out the case on one with a special cutting tool, or using an adapter as shown in the video on another. The one shown in the video is pretty trick - I would like to see a tear-down after, say, 40,000 hard miles to see how it has held up. If you buy the LN upgrade kit, they lend you all of the special tools you need, no charge - YUGE Selling point. The word on the street is that they ALL work pretty well, and the sealed version should last as long as a clutch (typically, 50,000 miles) when you can easily replace it anyway, if you’re timid about making a hole in your $20,000 engine bigger to accommodate the larger, oil-fed bearing.
Both Chris and Rich opted for the sealed bearing “upgrade”. Both had heard that if you baby the engine, the IMS will fail prematurely. If you hammer on it regularly, it won’t fail as soon. Sounds like a perfectly normal Porsche thing, to me, and Chris’ will most assuredly fail much later than Rich’s. 🙄
Both are opting for the stock, Porsche clutch, too. I mean, if the engine and flywheel are both on the shop floor, wouldn’t YOU put a new clutch in?
Not the only problem. I did the IMS bearing replacement with the L & M bearing about 5 years ago...and the clutch, only to have the engine bomb due to hydraulic cam chain tensioner failure. A $950 part that is easy to replace, but Porsche had no inspection interval recommendation. My car had 130k miles and was running like a new one.
'til then
Yeah sometimes we feel so good about chain tensioners then they give way and a fiasco occurs. The other guys change a belt regularly. 
The IMS repair Ant does on Wheeler Dealers uses the IMS bearing kit designed by Jake Raby.
Agreed, Gordon, the engines that seem more inclined to have the problem are the occasionally-driven garage queens. Regularly driven and flogged cars as a whole do not have trouble.
Crossroads: '05 997.1 C2S with PCCB's (good for street, bad for track) with all the go fast options and 90K miles and the original clutch. A redline a day, keeps the doctors away. Per my S/N, the IMS is 'upgradeable' and there is 'no need' to split the case. However, one never knows until the bearing is removed and inspected - so I've heard. I also read that Porsche phased in the 'upgraded' IMS mid 2005 including all replacement engine if one had the unfortunate luck to need a replacement engine for a number of reasons. My 997.1 C2S (3.8) was manufactured in July 2004 and bought in September 2004.
I didn't plan to replace IMS, but the clutch needs to be replaced. BTW, I have had NO problem sleeping at night the past 11 years. But while I'm in there...well, you know how it goes.