IMS Fix / Replacement - need some advice

[jsg1206]

I would imagine this question has been asked numerous times, new user, but would like some "expert" opinions. In February, bought 1999 Boxster 986, 5speed with 74k miles, like new, drives great engine feels very strong no slippage, had Rennsport Porsche Works here in Sealy, TX give it a good "once over", replaced oil, filter, etc. said no major issues they see - Car now has 76k miles on it. Their opinion on IMS issue was replace oil / filter every 5,000miles, drive the car "like you stole it" don't worry about it.

I spoke to another shop in town about "performance" upgrades to the car, exhaust, etc. the first thing they asked "have you replaced the IMS"??? Gave me the scare tactic about dropping the transmission and really see what is going on if anything before talking performance upgrades. As you would expect with a 99 boxster, not an expensive car, but love it and would hate to "lose it" - what should I do? appreciate any feedback

[jklaspok]

I don't think you have much to worry about. From what I've read on this forum, is the earlier cars such as yours have the more hardy and reliable double row bearing. Also in general the IMS issues occur on the lower mileage cars. I had the bearing replaced on my 2000 at roughly 100,000 miles. It was double row and in great shape. If nothing else, it gave me peace of mind.

[Giller]

Use the search function and do your reading. Lots and lots of opinions on the IMS.

It's a known issue with the car. How much of an issue is debatable as there are not any firm facts as to what percentage will break. 1%? 5%? 10%? Heck, you can see that just from the two opinions you've already gotten.

IMO it's all about piece of mind and budget. Fixing it MAY save you a lot of money. Then again, it MAY last the life of the car and it will be money wasted. Who knows? Nobody, that's the problem.

[jsg1206]

thanks for the feedback, if I decide to add some performance upgrades (further stressing all moving parts), probably makes sense to at least have it "thoroughly" checked...... will keep you posted on what I find out

[mikefocke]

Shops are there to sell you things and the IMS update is one of them.

You have an IMS that has made it this far. That is a plus.

Your IMS is probably the best of the three Porsche designs (unless it is a Porsche replacement engine and then you can't tell until the transmission is off). That is two probable pluses.

There are no reliable statistics on the failure rate of your IMS's probable first generation design. Anyone who gives you some stats is guessing based on the stats from a lawsuit that involved a different IMS design.

If the failure rate were as high as the second version, the lawyers would have also done a class action for the original (just like they did for the single row second version) and we'd have statistics.

Does it make sense to put that much money into a car worth maybe $8k when there are 28 other known modes of failure? Why aren't you addressing those first when their failures far outnumber the failures of this IMS design? What if you totaled the car tomorrow?

If I were putting $10-24k into the engine to upgrade all the major failure points I'd definitely be replacing the IMS. But to do it when you don't need the transmission removed for another reason (clutch, etc) seems to me to be overkill.

Which is not to say it couldn't fail tomorrow. But you can say that about every part. I have two recalls on my two Toyotas right now. No car is immune from random failures or ones that show up 10 years later.

Only you can decide what the right thing for you to do is. You have a different risk tolerance than I do ... guaranteed.

(I've followed this issue for 7+ years on at least 7 forums on 3 continents, talked to several of the developers of the replacements. I owned a '99 and a 01S. I didn't.)

Use the right oil, change it frequently (much more frequently than the Porsche recommendations) and drive it so it gets warm for a good while as frequently as you can.

You know more about this car and its engine that you would about most cars because it is such a great car and we car nuts love it so.

[Nmbrsix]

On a dual row car? I wouldn't worry about it as much. 1%/vehicle year, I'd consider adding the IMS Guardian--or just change your oil more frequently (every 3000mi) and check for debris.

[emore93]

I just replaced a single row that had 122,000 miles on it and it was in very good condition.

With those miles I would wait till a clutch change before I would worry about changing the IMS bearing.

Like others have said..."if it made it this long..."

That was one of the reason I looked for a "seasoned" Boxster.

[CrisZenithBlue]

i bought my 2000 Boxster base with 111.000k miles on it. the clutch still had some bite on it but it was getting stiff so i figured if i was going to keep the car might as well enjoy a fresh clutch from the start and do the IMS as well. got a new front mount in there as well because it was trashed. double row IMS was in great condition and honestly i wouldnt have opened it up if it wasnt for the clutch. with a 1% failure rate the money would have been sitting cozier in my pocket. 1% is nothing..

unless you need to open it up save your money. if you total it tomorrow you would kick yourself.

[j.fro]

my 2000 Box S has the dual row with 177,xxx miles on it now.
At 65,000, I pulled the dual row IMS from my 99 C4. It was perfect. I replaced it with the LN ceramic dual row. Probably could have left it alone.

[spendy]

One more data point. I replaced an IMS on a '98 engine with 70K miles. While the bearing was in great shape, it had motor oil inside, indicating the seal had failed. I have no idea how long it would have lasted, but my understanding is seal failure is the beginning of the failure process. If it were me and I was planning on keeping the car for a while, I would probably replace. If the budget did not allow replacement, routine oil filter checks and oil analysis would improve the odds of catching a problem early.

[Duezzer]

Spendy had the same thing as myself - I have a 99 with a dual row - @ 120,000 km I did a clutch job - While doing that I took the time to pull the cover on the IMS - the seals had failed - I ordered a new IMS bearing kit and installed it - a bearing like these are sealed and have EP grease in them, when the seal fails motor oil gets into them - the motor oil washes out the grease.

From what I have read the motor oil is pushed out of the bearing by centrifugal force and bearing runs dry as there is no oil feed.

I suspect one could do the EPS oiling system if the seals were leaking enough. This way they would always have lubrication.

I do not really know if this would work and I am not suggesting you should go this route.

I have 5000 km on the full EPS system but that is not enough time to say their system is any good.

I did quite a bit of research into their system and liked the layout of it. The only thing I don't like about the system is that it uses non filtered oil from the oil pump. Having said this I don't believe it is really that big of a deal.

[mikefocke]

There are 10k+ LN bearings running just fine for years and miles with the seal not there by design. Only immersion at rest and mist while driving to lubricate them. Ball bearings don't want big amounts of oil, they want to not have to push it out of the way.

On the dual rows, if the seal has failed, if it fails enough and if the engine is driven strongly enough and frequently and there is clean oil, there is very often no problem. Have seen 200k miles and when pulled some oil still in the bearing.

[Luv2Box]

Keep in mind that after all this advice is given the only person who pays is you. Make your own decision about your vehicle because if the IMS does go all the advice givers won't chip in to cover the bill.

[mikefocke]

Originally Posted by Luv2Box

Keep in mind that after all this advice is given the only person who pays is you. Make your own decision about your vehicle because, if the IMS does go, all the advice givers won't chip in to cover the bill.

And you'll seldom know after it was done if it was truly needed.

Yep, all about risk tolerance. We each have a different one. And a different bank account. While someone might shrug their shoulders and just buy a new engine, others might agonize or struggle to come up with the cash.

There is, of course, also risk associated with choosing a specific kit to use and even which mechanic to do the job.

Figuring what preventative maintenance to do is always hard.

Good luck in whatever you decide.

[Luv2Box]

Originally Posted by mikefocke

And you'll seldom know after it was done if it was truly needed.

Yep, all about risk tolerance. We each have a different one. And a different bank account. While someone might shrug their shoulders and just buy a new engine, others might agonize or struggle to come up with the cash.

There is, of course, also risk associated with choosing a specific kit to use and even which mechanic to do the job.

Figuring what preventative maintenance to do is always hard.

Good luck in whatever you decide.

"When you come to a fork in the road take it."
Yogi Berra

[Duezzer]

Having done more reading on the dual row lack of failure I don't think I would of done the IMS upgrade when I did my clutch with the information I have now.

I would of installed a gardian and kept an eye on my oil filter on every oil change.

Prob would of installed a magnetic drain plug and for the $50 I still may.

On thing that does rattle about in my head is if the seal on the bearing does fail and breaks into pieces I could see this causing oiling issues.

I am glad I made the choice to do the change but not really sure it was required.

[BobRickel]

I bought a 1997 Boxster with only 40k on it. I knew about the IMS issues and being a 97-99 I knew it was the better of the designs and had the lowest failure rate but who knows. The car was still 18 years old so for peace of mind I went ahead and pulled the motor (tiptronic trans) and replaced the IMS with the EPS system. I also replaced the front motor mount, the AOS tank, plugs and tubes, water pump )already had some wobble with only 40K), Belts, all hoses, and filters and the rear main seal. That was last December and I have put 12,000 worry free miles on it since then. It was worth it to me to have the peace of mind to know I can jump in and do 1000 miles without worrying about any of these items.