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YOUR RESEARCH996 still on original IMS 120,000 miles
Leading reported evidence
Replace bearing
Performed · outcome unconfirmed
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Suggestion
I feel that I lowered my risk of a catastrophic failure by replacing the bearing.
Leading evidence: 'Replace bearing' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check imsb or seals' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Performed · outcome unconfirmed
I waited until the clutch was replaced, which was right around 105K miles.
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Performed · outcome unconfirmed
I had the IMSB replaced in my 996 with the LN ceramic bearing.
I have a spare engine ready to go in should I need it, but the car is a $10k car with that mileage, whether I put the spare engine in, the original keeps going, or I replace the IMSB.
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Performed · outcome unconfirmed
Anything else is just a guess as Porsche hasn't released the numbers, but has replaced many engines.
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My clutch and IMSB got replaced right before I got it.
I have a spare engine ready to go in should I need it, but the car is a $10k car with that mileage, whether I put the spare engine in, the original keeps going, or I replace the IMSB.
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An IMS upgrade is $2000 and I don't even think that is expensive for a car that msrp starting around 75k. Although if your IMS does go you will certainly need that Cayenne Turbo.
I did the conversion at ~44K miles mostly due the paranoia and the potential affect on resale value. It cost me $5200 but that included the clutch and other stuff that you may as well change if you do the bearing. But no evidence of failure or pending failure on mine. I am glad I did it, I guess.
I mean you should have had the clutch done somewhere in that 120k miles, if you do the clutch and don't replace the IMS/RMS while you are in there you are nuts. My clutch, flywheel, AOS, RMS, IMS was $4200 out the door, sure I could by a beater for that but I won't be able to buy anything if the IMS goes because I will need a new engine. I have a dual row IMS as well which seem to fail less but too each their own.
You can rationalize it all you want to make you feel better about spending that money. I made that mistake once doing it on the boxster. It was unnecessary. I didn�t spend $75k+ on a new 911 so there�s no way I�m spending that kind of money on a 3% chance. But your mechanic will thank you for it though.
I also didnt put in Mobil 1 either.
10k miles once a year oil change is enough for me.
6 years ownership starting at 60k miles. Now 120k
Wear item was the belt, plugs, and water pump. Fuel pump failed at 110k.
Add gas gas and go! It�s only a car. Don�t baby it.
Cars depreciate, maintenance doesn't. A $75k car 20 years ago still has $75k car maintenance. No one buys an old Ferrari and says "wow this thing is 25 years old, I don't need to do engine out service now.' That is because if you don't a belt snaps and you have a very pretty paper weight. Its great your IMS hasn't had issues and nobody wants it to but its silly to come in here and try to rub it in peoples faces.
I think people already know it's a low percentage chance. Not saying this thread is pointless but I've seen this whole should I or should I not replace IMS thread countless times and I've only been here a few months..Replace if you want or take the gamble, owner's choice.
If you look at the failure rate from the stickied post its 10% but that is a fairly small sample size. Regardless, 3% isn't even the number given in the lawsuit, its 8% which is absolutely unacceptable for a vehicle. If someone told you that you had an 8% chance of your airbag exploding and killing you then you would probably opt to have it fixed.
That used cayenne won�t save you any money, you better get a second job and a Toyota so that you can drive to those jobs to pay for your Porsche collection.
Don't buy homeowners insurance because the chance of your home burning down or flooding is very small. Don't ever get a physical because disease is a BS scare tactic used by doctors to get your money.
The failure rate is 0% if it hasn't happened to you and 100% if it has. Anything else is just a guess as Porsche hasn't released the numbers, but has replaced many engines.
When I think back over how much money I have wasted on auto insurance, 50 years and never a claim, I could be driving a Lambo and not a 996. Why ever buy auto insurance if you never have an accident? An IMS upgrade would have been a lot less money than the wasted premiums.
I agree with you, kind of. If these M96s only had the IMSB issue, I would change it. However, since they are plagued with so many issues, I think spending so much on replacing the IMSB is a waste of money.
I wish my state didnt mandate having car insurance. If they didn't, I wouldn't buy it.
Umm,, just a small point,, the 8%,,, is it per total production volume, or a 8% fail rate per year of the cars in use,, because that's a hell of a a difference.
The 2.4 GM ecotech has ring and bore problems and ,,,, a timing chain issues that destroys the engine.. Seems somehow familiar...
Oh and GM has lost a class action and has to provide coverage on them..
My 2003 C2 cab has 80K on it. I’ve owned it for two years and it has the original IMSB (as far as I know). Planning on replacing the clutch this fall and will install the IMSB from Pelican Parts as well. I figure why not spend the extra $189 while I’m in there anyway.
The 8% is laughable. So many bearings have been changed prior to failure that the 8% number is useless. What percentage of cars that had bearing changes would have failed if left untouched? How many of those car would have happily run 100k miles on the original bearing? We have no idea.
The real question is what percentage of cars with original, untouched bearings have failed and at what mileage? Only with that information can you gauge risk.
$2000 - $4000 for a Cayenne Turbo? You're the smartest shopper I know.
That's great. Public service announcement. Good to know you have some common sense left...
3% ? Where did you find that figure? Never mind.
smugnorance alert...
Who said it's a 3% chance? The lawsuit where Porsche released the numbers about how many of these cars needed engine replacement was a long time ago now. Is it still 3%? The seals on these bearings fail, but if you are lucky that the oil has kept the ball bearings from degrading, that is still a failed bearing.
It seems common sense to me to spend $2K on fixing something that could cost $20K to fix, but that's just me.
at 120k miles your clutch must have nothing left on it by now; you'll have to put a new one in so why cheap out by not replacing the IMS while you're in there? plenty of options now, you don't have to spend a ton of cash
Must be nice! I wish I could take a $20+K gamble and roll the dice just to save $500. (doing it with clutch) makes no sense to me...In fact it seems very foolish, what's the wife think?
Not (yet) a 996 guy,
I wonder if an endoscope could be used to check the IMSB or seals
on a 996 via some inspection window, avoiding the need to drop the transmission, etc. Thoughts?
Even with the trans out and the cover off an inspection really doesn't tell you anything. Best way to check it is to spin it with your fingers...after you've replaced it with some sort of upgrade.
I had the IMSB replaced in my 996 with the LN ceramic bearing. I waited until the clutch was replaced, which was right around 105K miles. My original bearing also didn't show any signs of an impending failure based on a visual inspection with the naked eye.
I decided to have mine replaced for two reasons. First of all, I saved some money on labor since the clutch was being replaced. Secondly, bearings wear with usage. That's a fact. I figured that my original bearing served me well for over 100,000 miles, and a new bearing would likely do the same thing. Ultimately, it all came down to risk mitigation, just like insurance. I feel that I lowered my risk of a catastrophic failure by replacing the bearing. I didn't eliminate the risk, but I lowered it. For some people, lowering their risk is worth the money. For some, it's not.
3%???
Where did you pull that number from?
Ahhh, let me guess. You pulled it out of the area where the sun don't shine, didn't you!?
Question - Why start a thread like this? Come on, really!? Admit it. You don't care about spreading common sense because you have just opened your mouth and removed all doubt.
Look, there are two kinds of people in my world - those that have opinions and those that can back up those opinions with facts.
My challenge is to prove how you came up with such a number. If you can't, then pack up your puppet show and go home.
Nope, flywheel is in the way. If you purchase a 996 or other Porsche of this era, then it's best to get documentation when the bearing was swapped out. Of course, it's pretty easy to identify if the car have the IMS Solution on it. The special spin on oil filter adapter with oil feed is a give away.
What are the chances if his IMS goes he comes back and tells us? lol I am all for saving money but I just can't imagine purchasing a high-end Germans sports car and not expecting/wanting to put money into it because its only a 20k car. It's still a high-end German sports car.
I get what you are saying, my 99 coupe has 176k on the original IMSB, by all forum standards I should have replaced the IMSB in 2005, 2011, and 2017. At a cost of 2k-4k, I should have spent 6k-12k to prevent an IMSB failure, and will be due again in 2023. My 99 coupe is a Tip so no clutch maintenance to offset the cost/labor of IMSB preventative maintenance. I have a spare engine ready to go in should I need it, but the car is a $10k car with that mileage, whether I put the spare engine in, the original keeps going, or I replace the IMSB. I don't think it will ever be a collectable, but it is a nice ride and fun to drive, and I will keep driving. People compliment on it all the time, it looks nice and they think it is a 100k car, but they are not pulling out their checkbook to buy it.
You can certainly buy a 2004 Cayenne Turbo or S for 6k-12k, and they are solidly built, but will need brakes,tires,and driveshafts regularly, and coolant pipe updates (if not already done). I've seen plenty go into the 200k+ miles with no catastrophic failures.
The smart/safe money is probably on the "Solution". One and done. I actually had purchased 3 of them ( for my 3 m96 engines) when I found them at a ridiculously low price (about half), they were on the way but the seller realized the mistake and had the shipment returned to him midway..
How much is a 99 Coupe Tip with 176k miles worth? About 4k if the IMSB goes out, about 10k if it doesn't. It's worth more than that to me, so I will keep it on the road BAMN (By Any Means Necessary)
Life is a gamble, but you will not make it of here alive..
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Agree with many of the previous owners - my 2000 C2 IMS bearing was pulled to install the ceramic LN Engineering components at approx. 70k miles - the original appeared in perfect condition.
Said if before, saying it again.
Wish I'd left my '99 alone. Replaced the bearing with LN, now it is supposed to be done every 5 years/50,000 miles (or whatever it is).
Ah well.
Well, that's a bit of a loaded question, but I will try to tell you where I am coming from.
I believe the original IMS bearing didn't technically have a service life, correct? It was "permanent." And lots and lots of the dual row bearings are still out there with 100,000k+ miles on them.
I also believe the LN replacement is a very fine piece of engineering - but it has a suggested replacement window, based either on miles or time.
So...when it comes to my 5 year/50,000 mile window, I will most likely hold off until I need a new clutch. Maybe then I will install the "solution" rather than just the bearing.
This is poor logic. Everything has a service life, even if we pretend it is "lifetime"...like auto trans fluid.
In other words, the original bearing will last the life of the engine. This is true for about 99.5% of them. The other .5% will experience IMS bearing issues but will not grenade the engine.
Can the
original
1999 year dual row IMSB (reportedly quite reliable) be simply replaced instead of an aftermarket bearing? I'm told bearings have standardized numbers, such that a given design may be produced by various manufacturers, so what is the price of such a bearing? Not the aftermarket bearings commonly noted here (good as they may be), but an off-the-shelf identical dual-row bearing.
Anybody got the serial number off an original 1999 bearing?
I ask because while rebuilding a BMW alternator I priced its original bearings at a car parts store, and was quoted $26 for the big bearing, and $6 for the small one. The exact same serial number/manufacturer bearings in the exact same boxes were $6 and $2, respectively, at a Case farm implement dealer. It pays to shop around. So who made the original units used in the 1999 cars?
Are you suggesting that using a generic bearing would be more desirable than something like the LN Retrofit because the Retrofit has a stated service life and a generic bearing does not?
You're right, it is a loaded question. I wanted to be sure I understood your thought process. Turns out I was interpreting it correctly. Unfortunately, you did not pass the logic test.
4D4 correctly points out that all parts have a service life - even ones claimed to be good for the "life" of the engine. There are design flaws with the original IMSB. I'll not go into many details, but there is a lot of solid information out there on why this is so. As I understand it, there are seals on the bearing and it relies on pre-packed grease to remain lubricated. Either of these features have the potential to break down over time.
At least with the LN retrofit, the ceramic ***** are exposed to oil splash from the sump. The fact that LN recommends a time/ mileage service interval, does not mean it is less robust than the original sealed bearing. You'd have to read their explanation as to why they place those numbers on their products. As an engineer, I can appreciate what they have done as far as evaluating failures, then developing and testing their products.
Not everyone buys-in to their program and their products. In the end, it is your money and your decision.
Speaking strictly for myself: the more I read and study, the more I am inclined to stay with LN for my car. For what it's worth, my LN retrofit is nearing its replacement target. As you mention (bold), I will also wait until I need to get in there. I'm not going in there just to replace the bearing.
Exactly. Perhaps I was too tongue in cheek: The IMSB will last the lifetime of the engine in most cases. Unfortunately it is quite often the cause of death.
It's like engine oil. If you never change it, it will last the life of the engine. ;-)
Roller bearings are consumable items. They don't last forever. The bearing in the M96 is under a lot of stress, relatively speaking. There is a chain pulling on it in one direction with constantly changing speed of rotation and tension. The 2004 came with the smaller single row bearing, so the force on each individual ball and the cage that holds the ***** in position is higher, explaining the higher failure rate. Oil dilution of the grease in the sealed bearing it part of the equation too. I can understand not doing a special transmission out, or engine out, service to do the IMSB. When you are doing the clutch however, it makes sense to do the bearing.
I did get a big smile when I read you bought a Cayenne Turbo. Are you going to ignore the plastic coolant tubes and fittings on it? Of course, run to failure will probably not be as catastrophic. You will just be stuck on the side of the road, provided you shut it down before losing too much coolant.
I think it matters what bearing you have and if you have reason to go in after it.
I have a �99, a dual row, probably original, and 62,000 miles. If I have to separate the trans for a clutch or RMS or otherwise drop the engine, then I�ll do the IMSB.
If I had a small single row, I�d probably want to change it out sooner. If I had the larger single row, I�d probably wait it out, as those are not even serviceable...
Think about that - Porsche has a bearing that�s not intended to be serviceable, even after all this fiasco and lawsuit considerations. Kinda makes you think the original problem really was the small single row and the others aren�t really an issue.
Toyota and Jeep 5 speed transmissions had very common fifth gear bearing failures,,
sealed / shrouded bearing almost the same size and setup.. and just about 10% of them failed
between 80 and 120K miles especially if folks towed in fifth gear.
My clutch and IMSB got replaced right before I got it. When I need a new clutch, I’m getting the Solution. Then, I only need to lose sleep over bore scoring.
TC
I'm suggesting that the original factory bearing in the early '99 cars was not included in the factory legal/financial settlement because that original dual-row bearing has not been shown to be significantly unreliable to warrant replacement, i.e., it works well over time. Therefore, an equivalent or better bearing/seal of the same or better specs would suffice for a replacement, if needed at all.
I'm further suggesting that such suitable alternative may be available from a reliable manufacturer, at an attractive price, giving a 996 owner other more affordable choices for a replacement bearing, which may not even be needed.
If someone here will kindly supply the dimensions and part number(s) for the original '99 IMS bearing/seal, perhaps we can find a suitable and affordable duplicate.
People have been there, done that long before you arrived. This stuff has been hashed through over and over here and elsewhere.
You can Google some dude on YouTube that did this on his Boxster, based on the same line of thinking as you. Is it possible, yes.
Pelican sells a cheapo replacement set, if you are just trying to save a buck.
For the few additional bucks involved, and criticality of the bearing, do yourself a favor and just buy an LN Retrofit. If you can swing it, go to the LN Solution.
A lot of dudes cry about the price on an LN bearing but at 3-10% ( solution is closer to 10%) of the cost of a rebuild it�s pretty cheap insurance. Think about how much you pay in auto insurance over the life of the car if you don�t believe me. A 996 with a blown engine isn�t much more valuable than a totaled one.
Don�t like this fact, get a different car and it won�t be a concern.
"Think about that - Porsche has a bearing that’s not intended to be serviceable, even after all this fiasco and lawsuit considerations. Kinda makes you think the original problem really was the small single row and the others aren’t really an issue."
According to Porsche, none of the IMS bearings were ever serviceable!(or even supposed to be) - FSI and LN Engineering developed the procedure, tools and ceramic replacement bearings - they even developed a 3 row bearing early on (pre-"IMS Solution") - I wonder how many of those are still out there?
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