changed my ims bearing. was like new
 

So, I know this topic has been discussed sooooooo many times, but just wanted to give my feedback on the matter. I had been thinking about it for such a long time, and since people were saying that garage queens suffer the most Ims bearing failures, I thought id better just bite the bullet and get the bearing replaced.
So I bought all the parts I needed, including obviously clutch and flywheel and thrust bearing rear main seal,etc, since it makes sense to change your clutch once the gearbox is out, and got my mechanic to have it done for me. I have a 99 model so it was the dual row bearing, and I can say that the old bearing still looked absolutely new. No free play whatsoever, nothing, runs smoothly like the new one. I was expecting it to at least have some slack, but it was in perfect condition.
My car is a queen of queens. It has 75k miles on the clock and sometimes spends months without being used, so that's why I was getting worried, but as I said, turned out there was absolutely nothing to worry about since the bearing was still in perfect shape. Luckily, the clutch and flywheel were showing quite a bit of wear, so the gearbox didn't come off for nothing.
I know that some people were unlucky with their bearings, but I now believe that it just happens to a VERY small percentage of cars which maybe had a batch of defective bearings from the factory. Frequent oil changes I believe is a must, but if I had to have another Porsche with the famous ims bearing in the engine, I personally wouldn't worry about changing the bearing untill clutch needs replacing, and even then, I'd remove the flange and check for free play first, and if there isn't any, I'd just remove the front seal. I know some people here might not agree with me, but That's just my opinion! Thanks for reading.

Was the grease still in the bearing or had it washed out? If it washed out what was the oil in the bearing like?

Nice to hear.

I'm not going to touch mine I don't think. I've heard some people having a failed IMS bearing AFTER they've changed it, and it's written off the engine. Some people have had the original bearing and are over 200,000 miles.

So people have had them fail before and after changing them, and some people have had no problems on original and new bearings. But like you, I'll check mine when it comes to changing the clutch.

Good one though :)

The causes and modes of failure of the M96 IMSB are many and even now , not completely understood.
The responses to the risk of IMSB failure vary from preemptive upgrades that will easily outlast the engine to prayer.
It all depends if you want to rely on Engineering or hope. You are correct , many of the 'hope' guys have been lucky.
As for the "I replaced my IMSB and then the engine failed" cases - there are 14 pages of Instructions mostly single spaced with revisions and updates- that the average DIY guy seldom finds or follows to the letter. If these specific Instructions are ignored ,yes the new IMSB may fail,possibly with collateral damage. And then there are the essential ,expensive Special Tools that may not have been used ?
IMHO the main advantage of a pre-emptive IMSB replacement is that it is more likely you pass the pre-qualification test. Which is another problem - many IMSB replacements do not mention following the pre-qualification checks. So those guys are in the 'hope' category also.
So your cars with original and perfect IMSB's are gems !

No, grease was washed out, but oil in the bearing was totally clean

I hope I didn't make a mistake in changing the bearing after all!! Hehe, well, my mechanic followed instructions carefully, used the necessary tools, (that I bought), and followed torque settings etc. I'm hoping for the best. If the new bearing does fail, I guess it will be my fault for wanting to change it in the first place!!

I just did my bearing too. '03 S with 119k miles on it. The original bearing was as tight as the new Pelican/NSK bearing I replaced it with. I was expecting to see munched roller balls and the worst type of mechanical carnage imaginable when I popped the cover off, based on what I've read on this forum. But it was totally fine.

Now I have mixed emotions about the adventure - if I didn't swap the bearing, I wouldn't have been able to enjoy the car because of the "imminent catastrophic failure" that would always be on my mind. Now that I've swapped the bearing, I have piece of mind, but I've invested over 20 hours of work, and have a few broken exhaust bolts I need to deal with, and had to deal with the timing chain skipping both cams. So having the knowledge that the OE bearing was fine changes my perspective from it being a valuable preemptive replacement to a waste of time. But, or course, that knowledge was only attained after I popped the bearing cover off, which is 90% of the work of changing the bearing anyway. Blah, rant over.

Yep, my feelings exactly. Every time I used to hear a noise in the car I used to think the engine is going to go "kaboom" ,with an ims bearing failure. Now though, that I saw with my own eyes, a car that was typically in the group of most bearing failures, " garage queens with very limited mileage" I have a different idea. I would leave it alone until I REALLY have to drop the transmission for a clutch change and inspect it then. I know some people were unlucky, but I guess its with everything, you only care about what happens to you, and not anyone else. What I'm hoping now is that I didn't do the wrong thing by replacing it, I hope that I didn't wake up a sleeping dog!!

One of the alleged modes of failure is the grease seals on the bearing become compromised and allow oil in to the bearing .There is eventually a cascade of horribles that result in IMSB failure.
This scenario has been covered in previous posts.
If they are correct ,your replacement was very timely.

Then again it's been known for this oil to lubricate the bearing, thus making it last longer.

IMS bearings are weird...

Well, it was a double row bearing. ;)

I would only change an IMS if i had to change the clutch. What i do is change the engine oil yearly. If it helps - i don't know. Makes just sense to me.

Regards, Markus

If the bearing no longer had grease inside, then it wasn't perfect.. It was at Stage II failure, there are 4 stages total.

Don't judge an IMS Bearing by it's cover... Until its cut apart and the grooves and balls precisely measured, you can't grade the bearing.

Go out right now and buy a Powerball ticket. You some lucky dude.

I very much doubt that ��