996.1 Fact check
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996.1 Fact check
I am looking at MY99 996.1 with 33k on the clock. Lucky enough to finally find a car I could see service records for most of the history. I have however read two things in postings I am wanting to see if anyone can verify. I have read pre 2000 996 has a dual IMS bearing and less prone to failure. The second is the 3.4 engine is not prone to bore scoring. Not having found much more than postings on social media making these claims l was hoping someone may have more information on this. Appreciate any insight anyone can provide.
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From: Hudson Valley, NY
Be ready for many on this board to tell you you'll need to spend $500-$1k on this car before you buy it to make sure you should buy it, then have another $10k ready for all the things you'll need to do after you buy it.
Data has shown that cars with a dual row are less prone to failure. I don't think the bore scoring has been proven to be any more or less prevalent.
Edit: I from previous posts you have already done the PPI thing with another car without good results. If you were willing to spend the money on the first one I can't see why you wouldn't on the next one.
Data has shown that cars with a dual row are less prone to failure. I don't think the bore scoring has been proven to be any more or less prevalent.
Edit: I from previous posts you have already done the PPI thing with another car without good results. If you were willing to spend the money on the first one I can't see why you wouldn't on the next one.
Last edited by hbdunn; Dec 26, 2022 at 05:32 PM.
Racer
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While it's true that the dual row IMS bearing used in the 1999/2000 model years is more robust and less prone to failure than the single row used in the 2001 to 2004 models, it is still a wear item and should be replaced at the same time as the clutch, around 60k miles. Also, a Pre-Purchase Inspection is highly recommended and would include inspection of the bores for any signs of scoring. Considering the consequences (read $$$) of bore scoring, due diligence is warranted. Best of luck with your buy, sounds like a strong candidate!
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Read all of this first, and don't start new threads on the IMSB https://rennlist.com/forums/996-foru...his-first.html
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While it's true that the dual row IMS bearing used in the 1999/2000 model years is more robust and less prone to failure than the single row used in the 2001 to 2004 models, it is still a wear item and should be replaced at the same time as the clutch, around 60k miles. Also, a Pre-Purchase Inspection is highly recommended and would include inspection of the bores for any signs of scoring. Considering the consequences (read $$$) of bore scoring, due diligence is warranted. Best of luck with your buy, sounds like a strong candidate!
Thanks Weazer, yeah this is my third car I have looked at. Others were dropped, one for bore scoring on a 2005 in Scottsdale and the other was ticking pretty loudly and the pipes looked pretty black that I found in Dallas. I've spent more on PPIs then I care to admit at this point. Finally found a local car, not many where I am in eastern Iowa that I found. I am getting ready to send this one out for a PPI as soon as weather permits. The interior trim is all I have found that needs work, it has the wood trim option and most of it has cracked or peeled. Appreciate the input and information on the IMS.
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Be ready for many on this board to tell you you'll need to spend $500-$1k on this car before you buy it to make sure you should buy it, then have another $10k ready for all the things you'll need to do after you buy it.
Data has shown that cars with a dual row are less prone to failure. I don't think the bore scoring has been proven to be any more or less prevalent.
Edit: I from previous posts you have already done the PPI thing with another car without good results. If you were willing to spend the money on the first one I can't see why you wouldn't on the next one.
Data has shown that cars with a dual row are less prone to failure. I don't think the bore scoring has been proven to be any more or less prevalent.
Edit: I from previous posts you have already done the PPI thing with another car without good results. If you were willing to spend the money on the first one I can't see why you wouldn't on the next one.
Thanks for the info on the IMS. I couldn't understand why the 3.4 would be less prone, temps are what the temps are and with all the ideas on why the scoring happens I couldn't see why the slightly smaller engine would make a difference. But I am no mechanic so why I decided to go to the boards and see what those with more knowledge had to say.
Thanks again and much appreciate the info. I just want to make sure I have done everything I can to ensure I am getting as solid of a car as I can.
Burning Brakes
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Thanks for the info on the IMS. I couldn't understand why the 3.4 would be less prone, temps are what the temps are and with all the ideas on why the scoring happens I couldn't see why the slightly smaller engine would make a difference. But I am no mechanic so why I decided to go to the boards and see what those with more knowledge had to say.
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Dual row IMS is more robust, but when they fail they shed more metal.
They can and do fail.
The percentages “reported” in the lawsuit are out of date.
Yes, 3.4 does not bore score as easily as 3.6 M9x or 3.8 M97, but that doesn’t mean never.
They can and do fail.
The percentages “reported” in the lawsuit are out of date.
Yes, 3.4 does not bore score as easily as 3.6 M9x or 3.8 M97, but that doesn’t mean never.
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Thanks for the info on the IMS. I couldn't understand why the 3.4 would be less prone, temps are what the temps are and with all the ideas on why the scoring happens I couldn't see why the slightly smaller engine would make a difference. But I am no mechanic so why I decided to go to the boards and see what those with more knowledge had to say.
Thanks again and much appreciate the info. I just want to make sure I have done everything I can to ensure I am getting as solid of a car as I can.
Thanks again and much appreciate the info. I just want to make sure I have done everything I can to ensure I am getting as solid of a car as I can.
Bore scoring less prone on the 3.4L, had a different cylinder liner that was changed going into the 3.6L (Alusil vs Lokasil I believe). 3.4L as noted aren't invincible, but failure rate is much smaller.
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From: Earth (Philly Burbs)
You can add a few thousand for labor if you’re having a shop do the work.
Don’t have it, so I have no first hand experience dealing with it.
But everything I’ve read seems like it’s difficult problem to deal with.
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Three Wheelin'
Joined: Oct 2018
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From: PA
Always good to plan for any fixes when buying a car. Simple answer is yes these things are less common on the 3.4 but it still happens. If a PPI checks out then its basically just bad luck if it happens at some point.
Nordschleife Master
Joined: Jan 2013
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From: SoCal
If you buy a 996 I know a guy that knows a guy that has a connection with another guy that sells a super special mix of, well you really cant call it oil but it acts like it
It will save your 996 poorly designed engine
Well at least that what I have heard
For life of me I dont why someone would consider buying a 996, ever
But if you do, start removing all the good parts that havent yet failed and replace them immediately
Lots of great threads on where to start on the list
Ive done all 51
It will save your 996 poorly designed engine
Well at least that what I have heard
For life of me I dont why someone would consider buying a 996, ever
But if you do, start removing all the good parts that havent yet failed and replace them immediately
Lots of great threads on where to start on the list
Ive done all 51
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From: Earth (Philly Burbs)
The IMS bearing, AOS and water pump have been working great for last 23 years.
Preventive maintenance is a scam, just replace that stuff when it breaks.
Plus you can use that money for some wider wheels and a big wing.
And don’t buy into that “premium” gas conspiracy either.
