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IMS bearing replacement help please

my996

Well-known member
Joined
24 Dec 2012
Messages
61
Hi everyone I have owned my 996 3.4 tiptronic 1999 for over 4 years. It has covered 85000 miles and it has not had the IMS bearing replaced. The question is: should I get it replaced and what are the symptoms I should look out for should it start going bear shaped? Is there a set cost for replacement or how much approx should I be expected to pay? Also any suggestions who could carry out this task, I live in the dumfries and Galloway area in scotland.
Many thanks for you help and advise.
 
The 3.4 has the most robust bearing in the 996 range. It's a dual row bearing so in my opinion, better suited than the later single row bearing in the 3.6

If it's lasted over 50k miles it'll be fine - forget about it and enjoy the car.

:thumb:
 
Agree with Alex.👍If you want reassurance give Steve Winter at JAZZ a call. He did the PCGB 996 Tech Seminar recently (along with others but he did most of the discussion) and was very informative on this. The two row appears to be the most robust design. He is a very approachable guy and am sure he would be happy to talk with you and give his experience. There is talk of the seminar being released on line watch out for it, well worth a view lots of informative info
 
Well done on buying the best iteration of the M96 engine. I'm biased apparently, but a dual row IMSB and ferrous coated pistons (on most) means they escaped the issues afflicting 3.6, however there were some faulty castings.

So yeah just leave it.

On such an old engine theres loads of things that could implode, the IMS bearing on a 3.4 is not perceived here to be a bigger risk than other stuff.
 
I was advised to check the bottom of the oil filter housing for any fine chrome metal deposits when draining the oil as this would be a sign of wear in the IMS bearing other than that with the dual row bearing all should be OK.

Mine had a new clutch, flywheel etc @ 85K miles and all was well on inspection its on 91K now and runs as it should.

*
*
Del.
 
Thanks everyone for your replies.
I keep reading in various magazines and write ups that it is a weakness of this 3.4 engine and it's only time before it let's go!!! I really wish people didn't write scaremongering stories if not true as it ruins the enjoyment of owning and driving this fabulous car...almost waiting for something to go wrong! I'm sure it is effecting the values too!
As I said I appreciate your help and advice guys.
 
my996 said:
I keep reading in various magazines and write ups that it is a weakness of this 3.4 engine and it's only time before it let's go!!!

And the experience of owners is that this is incorrect.

The American litigation showed that the 3.4 IMSB failure rate was far far below the 3.6.

Porsche economised on this bearing in the change to 3.6 and it ruined the reputation of all M96.

Thats not to say it doesn't ever fail on 3.4 cars..... just that theres loads of things that could go wrong on a old engine, the bearing is just one.

------

The 3.4 got a bad rep early on due to faulty castings (usually a leaking RMS or a cracked head). These will have all showed themselves by now. Oil weep from RMS is not really a problem unless you are OCD about tiny drips.

-------

The late 3.4 and the 3.6 got a plastic piston coating rather than the ferrous of the early 3.4, this breaks away causing premature bore score on those cars.

Something else the mags always fail to report on.

-------

The M96 is one of the greatest naturally aspirated engines of all time. If it wasn't for the issues above it would be widely heralded as such.

ENJOY IT!
 
Here's some info. on members 996 cars that I collected over the last 2 years:

failure%20distribution1610308jpg_zpsd82nafi0.jpg
 
This forum is brilliant and the members are great!! Such good info from owner drivers...fantastic endorsements to the 996 product!
This info should be sent out to the motoring industry media to put owners and protective owners minds at rest which in turn would allow full enjoyment... I can see the 996 becoming a desirable future classic rather than a car people don't want due to misinformation banded about.
Thanks again
 
You are right about the value of the forum but don't disbelieve everything on it.

There are only a small number of engines proportionally or statistically that have so far failed for one of a few weak spots in the design and manufacture - but as the mileages increase the chances do as well and the proportions/statistics go up.

There are those who exaggerate the problem and you are right not to listen to them - but on the other hand - if you do experience a problem (and I sincerely hope you do not) the forum once again is a great source of information about different solutions and specialists.

It can then be confusing because different people have different loyalties and you cannot be sure that a rogue dealer is not placing exaggerated credit about himself through the medium - or criticising his opposition unfairly.

However there is enough stuff on here to weed them out and follow advice and recommendations.

I hope you will never have to research a big repair but meanwhile take note of IMS advice, oil type, thermostat temperature setting and type and to make sure the car is fully warmed up before blasting it.

Good luck


Baz
 
Thanks Baz great info and advice.
 

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