mklein9

Tony Heyer has been my indie for about 25 years now and I wouldn't doubt what he says. However, it's a probability thing. My 2002 came "this close" to a massive failure. It was caught during an oil change after I installed a magnetic drain plug at Tony's recommendation, shedding metal like there was no tomorrow. There's a long story attached to this, but that's the summary for the topic at hand. Yours is a 1999 with a much stronger IMS bearing. I've done a lot of research and talked extensively with Jake Raby while going through this with mine, and from my understanding, for your case, I would recommend 1) Magnetic drain plug, 2) Spin-on oil filter to eliminate the stock oil filter bypass valve. But if you haven't had a failure yet, especially given you have a '99, it is unlikely you will, even with the low mileage.

Flat6 Innovations

@RSBro
Actually, I moved on from Unimogs a few years ago. I shifted my focus to armor, and tracked vehicles. Yeah, tanks and half tracks are more effective around here. Looks like you must be one of those "Must be nice" guys? What isn't "nice" is dealing with people that think like you-

Anyway, you are so misinformed that it isn't even funny.. Well, it kind of is funny.
I haven't sold IMS products, or had anything to do with the IMSB sales since 2011. I buy my IMS Bearings from LN Engineering just like everyone else does, and I also buy the tool kits like everyone else does. I did my part as the idea guy, and the developer. When that part was done, I checked out, and have not looked back.

Today what pays for tanks, and half- tracks isn't people that are afraid of failure buying products, its actually the contrary. Failure is what drives my business, and business is good. The more people that don't address failure before it happens, the busier that we become.

Today these people are part of two groups, the ignorant that had no idea these engines failed, or the ones that choose not to address things preventatively. (They think that it's "hype" or "fear mongering") I deal with the former, and latter on a daily basis, but the one things we no longer do here is preventative IMSR work- we don't have the time.

So, you might want to alter your signature, to be more accurate. Thank you.

BTW- I took the Sabre to Caffeine and Octane yesterday, and left the Porsche cars at home. It was a good time, and I actually enjoyed myself, which is much different than when I show up driving a Porsche~

Ron P

I bought a 2002 C2 Cab with 24,800 mi and replaced IMS with Single Row Pro as I recall. I now have about 50K mi .
I keep seeing “only 10%” failure rate for 996 IMS. I think that is actually a very high percentage. I don’t know what the real number is but a manufacturer that puts out a supposedly high quality product with that kind of failure rate seems pretty darn incompetent, irresponsible or malevolent to me .

moerbeck

2004 - MKII - 117K miles no failure. Getting it replaced with the clutch.

808Bill

10% is an old estimate. That number has increased as more have failed over the years and it will continue...

NuttyProfessor

When failures were happening under the warranty period, the data was closer to being accurate, but now that the newest of 996 are 10+ years out of warranty, most of these cars are probably NOT being serviced by the dealerships; therefore, an accurate percentage of IMS bearing failures can NOT be achieved. Hopefully people will get their head out of the sand and replace them as a precautionary step.

Flat6 Innovations

The percentages always have been, and always will be nothing more than vaporware.

The data that is required to create a sum doesn't exist with any degree of accuracy.

The engines that were misdiagnosed are one big factor in this equation.

Today we see just as many failures reported as ever, and the majority of these people had no idea that the engine had an IMS Bearing, or what it even is. It seems the only folks that are experiencing failures today are the ones that aren't informed.

Every now and then someone that was "on the fence" about IMS Retrofit will have a failure. The one group that never admits they were wrong is the camp that says this is all hype, and then it happens to them. They never admit they were wrong when it happens, they just crawl under a rock, but I am able to figure out who they are from time to time.

Chris Back

1999 original dual row at 88k miles, replaced proactively. I say 'maybe' because 2 things seemed off when I pulled the bearing. First, there was pretty severe pitting on the inside of the flange, maybe normal, I am not sure. Second, although both seals were in place and looked good, when I pulled the bearing quite a bit of oil came out of the IMS, and it definitely had an off smell, not like normal motor oil. If the seals were truly working I would have expected no oil behind the bearing.

Nonetheless, replaced with the LN ceramic. The LN toolset worked great for pulling and installing. I am also replacing the AOS, water pump, oil hex drive shaft, and RMS while the engine is out, so a little while longer before its all back together. So much of the plastic has gotten very brittle over 20 years of heat cycles.

Bizmonq

Sorting out my new-to-me 72K 2002 996 C2 Cabrio Tip that had an RMS single row classic retrofit back in Sept 2013 at 59K. The service interval says replace the bearing at 4 years or 50K. Can someone explain to me why IMS Retrofit would advise replacing a bearing before achieving less than the rated mileage? A 50K bearing service life makes sense to me, but an apparently arbitrary expiry time does not. The car being a Tip means there is no periodic clutch replacement anticipated, so I would obviously prefer to wait until the odometer hits 109K or thereabouts before replacement, unless I am missing something? These bearings are open bath or have had the seals removed, right?

808Bill

I advise you to contact the manufacturer/seller of your bearing for an answer to your question.
Or google it and you'll see many links to the topic of discussion...

jmj951

Based on what I’ve read, that suggestion is because of the potential for oil problems in cars that are not driven regularly. The seals can only take so much, and then they start to degrade. With partial degradation, you end up with a mix of oil, grease, and water (from condensation) within the seals, which begins to corrode the bearing races, leading to pitting and ultimately to failure.

Bizmonq

Guess I am surprised it would have any inner seal at all, making it an open bath bearing lubricated by the engine oil. Forget using the factory bearing grease for lubrication, that's the root cause of the problem in the first place so I would think any retrofit kit would throw the inner bearing seal away. I replaced a 986 IMS bearing with the Pelican Parts kit several years ago and the inner seal was simply removed. That kit has just a mileage limitation - I think it was 30K, but no mention of a time limit since the lube is constantly being renewed each time the engine is run.

Anyway I reached out to RMS engineering for their thoughts on the subject. I'll be bummed if I learn that the classic kit is just a sealed bearing replacement with factory lube. No better than the Porsche original so what's the point?

jmj951

Definitely let us know which one it is. I had a new OEM single-row installed about three years ago (because the engine was apart anyway for cleaning due to a bad water pump failure and he was able to source a full OEM intermediate shaft with single-row bearing for early 996’s) and the engine builder pulled the grease seal on that one. Said he’s been doing that for years on 9x6/9x7’s and never had a problem with any of them. But there is still a risk that any crap in the oil (plastic wearing off from chain guides) could lead to its destruction as well, so I still plan to replace it regularly as a maintenance item.

dporto

RMS Engineering? Oh boy... 😬

Charles Navarro

Pelican recommends 3 years or 36,000 miles for their kit, whichever comes first.

All LN IMS Retrofit products are open bearings with no grease seals.