View Poll Results: Has YOUR car suffered an IMS failure
Voters: 1602. You may not vote on this poll
IMS bearing failure for your 996, Y or N? tell us (yr, 996 Mk1 or MK2 failure mode)
#571
Pro
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That was , in fact, the ONLY advice I gave.
I'm glad that you seemed to confirm one point of mine however - that it's the size of bearing that's more important than the number of bearing runs.
One thing owners need to look at is the value of getting their bearing changed relative to the cost of failure.
Say the odds of failure are around 12/1 and the cost is, say, £8-10,000 (?) and, in the UK at least, the cost of changing to a new bearing is £3-5,000. Is there value in changing the bearing without a reason ? On the face of it, no. Not if you're a good gambler at any rate.
However, what the odds don't reveal are the relative odds of failure compared to mileage done. It would be interesting to see that breakdown if anyone has the data.
I'm glad that you seemed to confirm one point of mine however - that it's the size of bearing that's more important than the number of bearing runs.
One thing owners need to look at is the value of getting their bearing changed relative to the cost of failure.
Say the odds of failure are around 12/1 and the cost is, say, £8-10,000 (?) and, in the UK at least, the cost of changing to a new bearing is £3-5,000. Is there value in changing the bearing without a reason ? On the face of it, no. Not if you're a good gambler at any rate.
However, what the odds don't reveal are the relative odds of failure compared to mileage done. It would be interesting to see that breakdown if anyone has the data.
Your financial analysis isn't comparable to what we see in North America. A complete bearing failure essentially means a completely ruined motor, with few exceptions. A new motor from my local Porsche dealer is $24k installed. Preventative maintenance EXCLUSIVELY for the smaller, replaceable IMSB would be less than $3k (under reasonable circumstances where you can drive your car to a nearby specialist).
The cost ratio can change significantly if you buy a rebuilt or salvage engine. The cost of preventative bearing replacement can go up significantly if it's a later engine with the larger bearing or you decide to do a LOT of other 'while you're in there' jobs, such as chain tensioners, AOS, coil packs, clutch & RMS seal, etc. etc. Many of those usually need to be done anyway.
Dealing with an engine failure would be financially impractical to a lot of 996 owners in the US. We see a lot of 986's and 996's go to salvage due to motor failures because of a combination of the cost to replace the engine and the decline in value.
The question/gamble is, can you realistically recognize an IMSB starting to fail before it damages your engine? I couldn't, I only had a suspicion that there was a problem due to oil leakage on the case in that area of the engine. I just got lucky that I had to take my engine in for unrelated maintenance, and the shop recognized that my IMSB had almost completely failed. They opened the case and pulled out the IMS assembly in one piece so we could see its true condition before the bearing was removed from the shaft (
With regard to your question about failure vs. mileage, there is no direct correlation and you'll never find any hard numbers, but the anecdotal evidence overwhelmingly shows the opposite of what you'd expect - that a rarely driven car is more likely to have an IMSB failure than a regularly driven car.
#572
Intermediate
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Yes, I agree. With your risk/reward ratios changing the bearing is a no brainer and it seems there is a difference between the US and UK. Changing the bearing over here costs a great deal more, yet the repair of a failed one appears to be cheaper.
The garage also mentioned that one of the problems is caused by Porsche themselves advising long periods between oil changes, especially early on in the engine life. Seems you can help things along and do preventative maintenance by changing the oil more frequently, especially early on.
As others have said, its a crap shoot but I still maintain its wise to be cautious, particularly when it comes to choosing the garage to do the IMS work.
The garage also mentioned that one of the problems is caused by Porsche themselves advising long periods between oil changes, especially early on in the engine life. Seems you can help things along and do preventative maintenance by changing the oil more frequently, especially early on.
As others have said, its a crap shoot but I still maintain its wise to be cautious, particularly when it comes to choosing the garage to do the IMS work.
#574
Instructor
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So the 2002 Porsche ims failed at 22k miles and engine replaced in 2012 that makes 2200 miles per year in 10 years. Something fishy about this Krazy post.
Last edited by NIACAL4NIA; 03-01-2016 at 11:23 PM.
#575
#576
#577
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Hi
I bought my 1998 C2 Tip with 92 000 km. At 95 000 km i fitted the Vertex IMS fix. Old bearing looked good as new. At the same time i did a trans fluid flush.
Now the car has a whine like a spaceship. Not a loud whine but just a slight irritating whine from the rear of the car. Tech cant figure it out.
Not sure if i should have just left it alone and not fiddled.
I bought my 1998 C2 Tip with 92 000 km. At 95 000 km i fitted the Vertex IMS fix. Old bearing looked good as new. At the same time i did a trans fluid flush.
Now the car has a whine like a spaceship. Not a loud whine but just a slight irritating whine from the rear of the car. Tech cant figure it out.
Not sure if i should have just left it alone and not fiddled.
#578
Instructor
#579
Instructor
#580
Instructor
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I guess it is time for me to chime in here. A new to me 1999 996 C4 with 48K miles and the shop just called and said that the IMS was in the process of failing. It has the dual row bearing in it. I am glad I decided one of the first things I was going to do on this car was get that done. Costly engine repair avoided. ![thumbsup](https://rennlist.com/forums/graemlins/bigok.gif)
Marc
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Marc
#581
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A new to me 1999 996 C4 with 48K miles and the shop just called and said that the IMS was in the process of failing. It has the dual row bearing in it. I am glad I decided one of the first things I was going to do on this car was get that done. Costly engine repair avoided. ![thumbsup](https://rennlist.com/forums/graemlins/bigok.gif)
Marc
![thumbsup](https://rennlist.com/forums/graemlins/bigok.gif)
Marc
These types of tactics further skews these types of polls, rendering it next to useless IMO.
#582
Former Vendor
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If you ask them to check the IMS, of course a lot of shops will tell you it's failing to get the extra guaranteed work. I mean what consumer is going to reject that work order or diagnosis, whether true or not. You should always ask for the original bearing back so you could inspect it yourself.
These types of tactics further skews these types of polls, rendering it next to useless IMO.
These types of tactics further skews these types of polls, rendering it next to useless IMO.
#583
Instructor
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
If you ask them to check the IMS, of course a lot of shops will tell you it's failing to get the extra guaranteed work. I mean what consumer is going to reject that work order or diagnosis, whether true or not. You should always ask for the original bearing back so you could inspect it yourself.
These types of tactics further skews these types of polls, rendering it next to useless IMO.
These types of tactics further skews these types of polls, rendering it next to useless IMO.
![Big Grin](https://rennlist.com/forums/images/smilies/biggrin.gif)
Marc
Last edited by lomax; 03-11-2016 at 01:10 PM.
#585
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