IMS Failure is not a Myth.

[jdiba]

Originally Posted by WhipE350

The one thing he was strictly not allowed to talk about was IMS.

Strictly from my own perspective ? I find this pathetic.

[thstone]

^ I agree with you completely. This has been discussed to death and no one really knows the numbers except Porsche and they aren't talking.

But I'd also caution about trusting the company that created the problem in the first place and has ignored it since then. Always remember that your service writer's paycheck has "Porsche" written at the top.

[KevinH1990]

Originally Posted by thstone

^ I agree with you completely. This has been discussed to death and no one really knows the numbers except Porsche and they aren't talking.

What do you think Porsche knows? I think they have good data on cars repaired under warranty or when they gave a "good will" adjustment on repair cost to the owner. They may have some limited data on cars that failed out of warranty, but I doubt they spend a lot of time or money worrying about it. So, perhaps they could extrapolate a failure rate from the data they have, but I doubt they have really good data on cars like mine.

Moreover, the failure mode and rate may be affected by the age of the cars. My car is 12 years old now. I'm not the first owner and I usually work on it myself or take it to an independent. Other than hoping I may one day buy a new Porsche, I doubt their accountants and MBA's can make a business case for chucking $10-15k at me to replace my engine if it were to fail.

[NoGaBiker]

Originally Posted by thstone

^ I agree with you completely. This has been discussed to death and no one really knows the numbers except Porsche and they aren't talking.

But I'd also caution about trusting the company that created the problem in the first place and has ignored it since then. Always remember that your service writer's paycheck has "Porsche" written at the top.

Thanks for the agreement, but as to the last part, his paycheck actually says "Jim Ellis Automotive Group" at the top -- I know because Jim is a neighbor, and he owns over a dozen dealerships covering 11 brands, of which Porsche is probably the smallest by an order of magnitude. I am sure that if Ellis was enticing their service writers to outright lie, it would be for the purpose of encouraging unnecessary expensive repairs, not for the purpose of discouraging necessary expensive repairs.

[fivepointnine]

2 failures on the same car with totally different engines leads me to believe maintenance/driving habits MIGHT be suspect on this vehicle!

[thstone]

Here is what I think that Porsche knows:

1. Failure mode(s) of the bearing
2. Conditions which accelerate bearing failure
3. Conditions which slow bearing failure
4. Statistical failure rates based on year and mileage curves

Porsche is an engineering powerhouse. I am quite sure that they have studied, modeled, and analyzed the IMSB problem quite well. The ultimate conclusion? In 2009, the intermediate shaft was designed out of the engine. No, IMS means no IMS bearing failures. QED.

[jcb986]

Well, I am going to add my to 2 cents worth here. I believe most failures come from Porsches with standard transmission. Why the failure, the Tip's produce less stress on the back of the engine as where as on a standard you would have more stress from everyday driving. That's why clutches wear out. I chose my pre-owned Boxster with a TIP just because of the cost of replacing a flywheel, disk, pressure plate and release bearing. I really enjoy my Boxster with a TIP. On the back side I also had a few words with a couple a Porsche mechanics here in Orlando about the IMS issue. Since the first Boxster they think that maybe one Boxster had an engine failure.

[JFP in PA]

Originally Posted by jcb986

Well, I am going to add my to 2 cents worth here. I believe most failures come from Porsches with standard transmission. Why the failure, the Tip's produce less stress on the back of the engine as where as on a standard you would have more stress from everyday driving.

While there may be some element of truth in this, there is a more basic reason; the total number of Tiptronic cars is a very small fraction of the total number of the Boxster fleet. As the result, few Tips fail simply because there are fewer of them to begin with. But they do fail.

Interestingly, there are more than just one or two single owner, multiple IMS failure reports; so driving style may play into what factors lead to the problem; but again, only one source has most if not all of the data, and they ain't talking.....

[fivepointnine]

Originally Posted by JFP in PA

While there may be some element of truth in this, there is a more basic reason; the total number of Tiptronic cars is a very small fraction of the total number of the Boxster fleet. As the result, few Tips fail simply because there are fewer of them to begin with. But they do fail.

Interestingly, there are more than just one or two single owner, multiple IMS failure reports; so driving style may play into what factors lead to the problem; but again, only one source has most if not all of the data, and they ain't talking.....

right, that is the point I was trying to make,that there are several cars I have heard of that have had MULTIPLE failures with different engines, but the same car, and you have a lot of cars that have NEVER had a failure,which leads me to believe there might be something to do with driving habits, maintenance, etc...Im almost wondering if this 996 might have even had a failure with a ceramic bearing

[Johnny Danger]

What would Shakespeare say ?

To replace ... or not to replace ... that is the question: Whether 'tis nobler in the mind to suffer the slings and arrows of outrageous fortune, Or to take arms against a sea of troubled IMS bearings. And by opposing it ? To die: to sleep; No more; and by a sleep to say we end ; The heart-ache of IMS failure .

[feelyx]

Has anyone taken a replacement engine or the 05+ apart and looked at the bearing? I would like to know if it is a greased or oiled bearing, 2 or 1 seal and the part number on it.

[feelyx]

I had done some research on the life span of the bearing Porsche used. According to a "person" in a bearing company that supplied Porsche with the IMS bearings, the 6204 has a limited life span. The bearing was shipped out with 1 seal missing and no lube in the bearing, so who knows what was used as lube, and who, what, or where... they used to snap on the other seal. Also, 1 more tidbit there is a percentage of lube used to the speed limit of the bearing. Example.. if the bearing has a limiting speed of 10,000 rpm, and you are running it at 7,500 rpm, then you fill the bearing between 33% to 50%. If you are running the bearing at 2,500 rpm, then you fill the bearing 50% to 66%.

Porsche should of left the bearing filling, and seal installation to the bearing to the mfg. and this would probably be a non issue. This research was done on the double row bearing used to '99, and if the bearing, was filled correctly, and not damaged on intallation, or overrev'd etc. should of lasted into 100k's with no problems. OH, and as soon as I mentioned "Porsche" the "person" shut up and would not give me anymore info.

[pothole]

Originally Posted by feelyx

I had done some research on the life span of the bearing Porsche used. According to a "person" in a bearing company that supplied Porsche with the IMS bearings, the 6204 has a limited life span. The bearing was shipped out with 1 seal missing and no lube in the bearing, so who knows what was used as lube, and who, what, or where... they used to snap on the other seal. Also, 1 more tidbit there is a percentage of lube used to the speed limit of the bearing. Example.. if the bearing has a limiting speed of 10,000 rpm, and you are running it at 7,500 rpm, then you fill the bearing between 33% to 50%. If you are running the bearing at 2,500 rpm, then you fill the bearing 50% to 66%.

Porsche should of left the bearing filling, and seal installation to the bearing to the mfg. and this would probably be a non issue. This research was done on the double row bearing used to '99, and if the bearing, was filled correctly, and not damaged on intallation, or overrev'd etc. should of lasted into 100k's with no problems. OH, and as soon as I mentioned "Porsche" the "person" shut up and would not give me anymore info.

Heh. Interesting story.

Personally (and I have absolutely no proof of this), but my view is there's way too much smoke around the IMS issue for it to be a minor flaw affecting a small number cars. All engine designs have minor flaws affecting a small number of engine.

You often read of Porsche employees not being allowed to talk about it. If it was a minor issue, there wouldn't be any need for secrecy because the potential liability would be small. On the other hand, if it's a major issue, the motivation to maintain strict discipline over who says what is critical.

But for me the most telling thing is that even if it's as low a, says, two per cent that's still very high statistically and certainly high enough that you would have expected Porsche to have rapidly addressed and to all intents and purposes solved the flaw.

When the problems with Nikasil liners became apparent in BMW engines in Europe, they changed the liner material. They also changed out bad engines under good will for getting on for 10 years.

I also wonder about the wisdom of messing with bearings that have proven longevity. Mine's on nearly 100,000 miles. Honestly, if you offered me a free upgrade, I'd have to think about it before taking it (well, assuming the fitter wasn't willing to replace the whole engine should the new bearing fail).

[thstone]

Originally Posted by pothole

I also wonder about the wisdom of messing with bearings that have proven longevity. Mine's on nearly 100,000 miles. Honestly, if you offered me a free upgrade, I'd have to think about it before taking it...

This echoes my thinking. When I had my clutch replaced at 92,000 miles, I didn't touch the IMSB.

[schnellman]

I had to laugh at the title of this post. Flat tires aren't a myth either, but I don't lay awake nights worrying about them.

[ohioboxster]

The TT doesn't have the IMS issue, right?

[Steve Tinker]

The TT (up to 2009), GT3 or GT2 Metzger engines are a different design to the humble M96/97 series - they don't have the IMS bearing but are much more expensive to manufacture....

[gregwils]

There are really two issues here. First, the probability it will occur. Second, the consequence if it does. The first is highly debatable. The second is not - cataclysmic failure.

The scenario here is very similar to the old air-cooled days, hydraulic tensioners were failing and destroying SC motors. Porsche introduced pressure fed tensioners which did address the issue. The first thing people (should) check when buying an SC is whether or not the tensioners have been upgraded to pressure fed. Ironically, the cost to have it done is pretty close to an IMS upgrade. No one wants to spend the money, but if you look at as an insurance policy, it really is a wise investment. My $.02.

[NoGaBiker]

Originally Posted by gregwils

There are really two issues here. First, the probability it will occur. Second, the consequence if it does. The first is highly debatable. The second is not - cataclysmic failure.

.

I suspect it's only catastrophic, not cataclysmic.

[mts]

Originally Posted by gregwils

There are really two issues here. First, the probability it will occur. Second, the consequence if it does. The first is highly debatable. The second is not - cataclysmic failure.

No one wants to spend the money, but if you look at as an insurance policy, it really is a wise investment. My $.02.

Good point. A big issue is if you happen to be someone in the 2%-20%, however you define the failure rate, you are looking at big $$ to get the car back on the road. As these cars get older, a good fix after a failure could in excess of what the car is worth. That is a terrible result.

My IMS did fail at around 20k miles. Porsche replaced the motor under goodwill, but since the new motor was unable to have the IMS upgraded at a reasonable cost each time I did the clutch (as recommended by LN with their bearing), I sold the car.

Whether 1%, 2% or 20%, the failure rate is unacceptably high, especially on low mileage cars and I can't think of another 1998-later car of any brand that has a catastrophic failure rate anywhere close to the M96 cars.