Dispeling M96 engine rumors

[Brian Porsche Tech]

I have heard a few people talking about what is being said on this forum, and how it is really freaking many owners out about their cars. I have been a dealer technician for 30 years, the last 20 of which have been with Porsche. I have torn down several M96 engines after failures, and have built several outside of my primary job as a dealer tech. I'd like to offer my input and share what I've seen to the forum, and in the process dispel some of the rumors that seem to be running rampant.

First, the intermediate shaft. This is NOT a hoax. Most of the engines that we have removed from cars have been caused by failure of the IMS bearing. There are several versions of the bearing that have been used across the production run of these engines. The early cars had a dual row bearing, which has proven to be fairly reliable. Then can the smaller single row bearing. This is where we have seen most of the failures. Starting around 2005 the factory started using a much larger single row bearing, and we have yet to see one of these fail. While I have not yet seen one of the aftermarket bearings, I have to assume that this is a pretty good idea as preventative maintenance, especially if you have a car with the smaller single row bearing. The latest, larger single row bearing cannot be removed without splitting the cases of the engine, since the bearing is actually larger than the hole that you would pull it out through. Replacing this bearing is not a complex job, and could be completed by any competent tech, with barely any additional labor while doing a clutch.

Second, clutches. Whoever says that these cars are due for a clutch by 30K is sorely mistaken. It all depends on the type of use the car gets and how its driven. We've seen plenty of client cars make it to 100k on the original clutch, and we've also seen some go bad by 30k. Whenever doing a clutch, you need to replace the flywheel, so the notion of changing the clutch before it damages the flywheel is a moot point, as you're supposed to replace it anyway. If it's not slipping, keep driving it.

Third, oil. While the factory endorses Mobil 1, there are better oils out there. Mobil 1 is not the product that it once was. At my dealership, we still fill with Mobil 1, but I don't run it in my personal cars.

Fourth, lifters. Whoever says that these cars all need lifters replaced by 60K must be smoking something really good! If this were true, any M96 powered car over 60K would be considerably down on power. I have seen several client's cars dyno'd with varying mileage, and some of the highest mileage cars have put down the most power! Also, keep in mind that if a car had failing lifters, it would be throwing codes. We have put lifters in ONE car, and did so after it started experiencing drivability problems and throwing codes at 110K. Also, I'd like to point out that were there any truth to this, all of the "evil dealers" would be pushing this service as it would bring in considerable revenue on the service side.

Fifth, head cracks. Some of these heads do crack. It is mostly limited to 3.2/ 3.4 heads, but we have also seen a few cracked heads on 2.5 and 2.7 engines. While they could probably be fixed, with potentially questionable reliability, by a head shop, at the dealer, we replace them with new.

Sixth, cylinder wall failures. This has largely become a problem of the past. Most experienced on 2.5 and 3.4 engines, we haven't seen a "D Chunk" failure in quite a while.

Overall, the M96 is a pretty good engine, with a few shortcomings. The IMS being probably the biggest. I see that the aftermarket has made upgraded IMS tensioner blades and oil pump drives, and I guess if you're building a motor the couple hundred dollars this adds could be considered peace of mind, though we haven't seen any of those parts fail at our dealership.

In terms of rebuilding these engines, while not as simple as a small block Chevy, they are nothing more complex than any other German car engine. Yes, you need some special tools and the service manual with some added notes, but its a job that any competent engine builder can perform.

Remember, any modern engine will experience very little wear if taken care of properly. Modern metallurgy, production techniques and tolerances, and modern lubricants have gone a long way toward making engines last well beyond 100K. The M96 is no exception. There is no reason why these engines should not last 200K. The highest mileage engine I have torn down had 120K on the clock, and the cylinder bores showed zero wear, main bearings had virtually undetectable wear, with the rod bearings showing mild wear. The largest area of wear in most new car engines are the heads. The 120K heads were in need of new exhaust valves and a valve job.

To everybody, don't sit home and freak out about your cars, go out and enjoy them the way they were designed!

[Adam]

Thanks for posting and giving your personal feedback Brian. I hope you come back as I'm sure people will have questions for you.

[kls]

Good post! You have summarized the issues and non-issues fairly and made me a little more comfortable with my car. I have a 2004 2.7, which had an engine failure at 10K, before I bought it. Hopefully the larger bearing was installed at that time.

[Boxtaboy]

Great post! Thanks for providing your insights based on your experience with these engines.

Originally Posted by Brian Porsche Tech

Overall, the M96 is a pretty good engine, with a few shortcomings. !

I've owned over a dozen cars in my 25 years of driving (some really nice, some junkers) - my 02 boxster s is the only one that has had 3 engines in under 80,000 miles.

The M96 is a shamefully poor design in terms of reliability - Porsche should have let Subaru build these engines for them.

[Adam]

One thing that I don't understand is why Porsche changed from a double row to a single row IMS bearing? Seems like they shoud've left well enough alone. The old addage "if it ain't broke don't fix it" comes to mind.

[Stroked & Blown]

Originally Posted by Adam

One thing that I don't understand is why Porsche changed from a double row to a single row IMS bearing? Seems like they shoud've left well enough alone. The old addage "if it ain't broke don't fix it" comes to mind.

They probably saved $3.00 per engine on the manufacturing side....wonder what the net of that move is after warranty claims.

I don't think I ever read a post saying the IMS failures are a HOAX. I have read the rate if IMS failures might be exaggerated. And I never read anyone claim the aftermarket bearings are proven more or less reliable than the factories.

[schoir]

Originally Posted by dalealan2001

It would ne nice to know how long someone has been a member of this board when they are posting....

The "join date" is at the top right hand corner of all posts.

Regards, Maurice.

[Brucelee]

Originally Posted by Fred Demara

I've owned over a dozen cars in my 25 years of driving (some really nice, some junkers) - my 02 boxster s is the only one that has had 3 engines in under 80,000 miles.

The M96 is a shamefully poor design in terms of reliability - Porsche should have let Subaru build these engines for them.

I think Fred is right on here. I love the Box but this engine and RMS issue has persisted for many years. Ditto, I have never had an engine go bad on me in my 40+ years of driving.

I had a 327 Corvette that I beat as hard as I could, all the time, everytime.

Hey, I was 17. The car had cheap oil in it and perhaps, didn't have enough at times.

Never missed a beat.

I think they call it robust?

My current Lexus is coming up on 140K miles. Just drove it 2000 miles from SD to Des Moines IA. Never missed a beat, didn't burn a drop of oil. The car is 13 yrs old.

Porsche can do better on the engine, no doubt in my mind.

[Cloudsurfer]

I think most of us can agree, that if you want long term reliability in a car, go Japanese, specifically, Honda or Toyota. Unfortunately, as reliable as those cars are, they're just not that exciting to me.

[JTP]

Just like Jake said, you can't make a blanket statement about everything. Honda and Toyota is known for reliability and so is VW to a lesser degree.

Long ago I had a Toyota Supra that gave me a lot of headaches requiring many long nights repairing. During the same time period I drove my boss's Toyota pickup truck that I drove hard and actually tried to destroy but it proved to be stronger than my attempts to kill it. I also own two Mk4 VWs, a 2000 Jetta and a 2004 GTI, both of which I bought new. Similar cars based on the same platform. I've had nothing but problems with the Jetta (powertrain, electrical, brakes, everything had issues) and the rod just went at 140k blowing the engine. My GTI has been trouble free (knock on wood) requiring only routine maintenance. I've also had a 928S and three 914s that were relatively trouble free and a pleasure to own. I haven't had the Box long enough to make any statement about reliability.

VW has a decent reliability rating but if I only owned the Jetta I'd curse VW for building a lemon like the Jetta but the GTI has given me a great ownership experience. Similarly, some Boxster owners have a relatively trouble free ownership experience while some unfortunate few have multiple engine failures and gremlin possessed cars. In general Porsche has a good reliability reputation (consumer repoerts gives the Boxster a much better than average rating) despite some design flaws. The same can be said for Honda, Toyota and VW.

[RGH]

I can't take it anymore, I'm losing sleep worrying about this and I just bought the car. anybody want to buy an '04 base w/ 14k miles on it?

[Samson]

Originally Posted by Brucelee

My current Lexus is coming up on 140K miles. Just drove it 2000 miles from SD to Des Moines IA. Never missed a beat, didn't burn a drop of oil. The car is 13 yrs old.

Porsche can do better on the engine, no doubt in my mind.

Heh, don't even get me started on Japanese (Lexus, specifically) vs. German consumer-level product engineering and quality. I love my Boxster, but let's get real - German cars are known for doing a lot of things very well, but these days, quality is not one of their strong points. Lexus wins that race by a country mile. (I type this as I'm looking for another IS300... best car I've ever owned.)


Anywho, this is an interesting discussion. I'm looking forward to reading more.

[Cloudsurfer]

Keep in mind, that with anything of this nature, the people who don't have problems with their cars don't come on these forums to ******************** about it. Therefore, the many Boxster and 996 owners that have actually accumulated significant miles on their cars are out driving them and not commiserating with other owners who have had problems. I would actually say that my Boxster has been one of the most reliable cars I've owned to date. I do realize, however, that many other owners have not had the experience I have, and if I were in that other camp, I'd be just as upset as the others who are.

Personally, while I think Porsche could have done some things different with respect to these engines, issues with plastic rear windows, window regulators, convertible mechanisms, etc are just part of the game with owning a car like this, and not related to engine problems.

[Jake Raby]

Mike, Lots of the people who contact us have high mileage cars.. A chunk of these have already had a replacement engine, but another good chunk hasn't and they still run fine.

BUT many have just bought the cars with high mileage and gotten them at very good prices because they have high mileage. The majority of what we create is applied to dual purpose DE and street cars that spend more time on the track than the street.. More and more high mileage (less valuable) Boxsters are being made into dedicated tack cars and these people not only want reliability but they also want and need more power.

To them the factory can't give them what they want and therefore the prices we charge for a more thoroughbred engine are much more acceptable. Boxster track cars that are prepped well bring more money than street cars with low mileage and that also lessens the pain from spending money on a blueprinted engine thats built for the application.

I will say that cars that make it past 85K generally won't see any of the standard failures that are most common.. The majority of the failure calls we get range in mileage from 30-65K with an occasional call from a 70K+ owner.

We have begun asking callers if we can record their conversations with us for comparison and posting later, so within 18 months or so we'll have recorded data that we've logged from notes as well as MP3 files from phone chats that can be posted... You'll see that its the same story over and over almost to the word.

You have to remember that only a small portion of Boxster owners are internet junkies.. We have a lot that contact us who have no idea what the prices we charge are or even what an IMS bearing failure is. They are referred to us by our ad in Excellence or by word of mouth as being "The guys that can do the repairs" so they call us absolutely unknowing.. In fact I refer more people to our site than already know about it and send messages of inquiry to us. Heck some people have a failure then go to the dealership and receive a diagnosis only to hear about some broken shaft in the engine and that triggers a google search and then they find out about us.

We are now approaching the time that heavily driven cars are having engines begin to wear out rather than fail.. These made it past the most vulnerable points and continued on to the point where they are consuming oil and making rattling sounds. The amount of these is much higher now than it was a year ago and we are learning from these core engines when they are dissected.

And now what we charge is very close to the factory replacement engines from Porsche, much closer than it was this time last year.. Our prices have stayed the same and even dropped as volumes have increased, while the factory engines continue to see elevated costs periodically.

The people who are purchasing the 986 to be recreated as a track vehicle are generally a little different than the 986 owner who drives the car daily.. Some have a Turbo in their stable or another 911 and they desire the 986 due to it's superior handling. Its also considered a somewhat disposable car if they were to slide off the track, crash and burn.. Then they rip off the suspension, engine and tranny and throw those into another high mileage tub that they might have purchased for as little as 3500 bucks... Then they do it all over again.

You don't see many of this personality type on the forums...

It all really boils down to luck.. So drive the damn car and just don't worry about it. If it breaks you do have options.(It could be worse if those options didn't exist.)

[schoir]

Brian:

Thanks for taking the time to unselfishly share your experience and your sobering perspective on these engines.

Hype and hoopla seem to be the norm on the net these days, leading to near hysteria in some cases.

Your post reflecting your 20 years of hands on experience with Porsches on a daily basis is invaluable.

The fact that you fairly evaluate the benefits of the IMS retrofits available speaks volumes about your uncommon lack of $$ driven bias.

Thank you.

Regards, Maurice.

[Cloudsurfer]

Originally Posted by schoir

Brian:

Thanks for taking the time to unselfishly share your experience and your sobering perspective on these engines.

Hype and hoopla seem to be the norm on the net these days, leading to near hysteria in some cases.

Your post reflecting your 20 years of hands on experience with Porsches on a daily basis is invaluable.

The fact that you fairly evaluate the benefits of the IMS retrofits available speaks volumes about your uncommon lack of $$ driven bias.

Thank you.

Regards, Maurice.

I'd imagine he gets paid by the hour, or salary, with no commission based bonus, so I don't think he cares where we spend our money

[Lil bastard]

It's always interesting how receptive people are to news they want to hear.

I'm not saying the OP isn't well meaning, or that he's necessarily incorrect. But rather than dispel any rumors I think he's only added more fodder.

Not that he isn't skilled, but we're talking about 1 tech from 1 dealership, and at least some of what he's said contradicts info and data coming from Flat 6 and LN Eng. and also from a source which long predates F6 and LNE and established info and fixes on some of the nagging issues of the M96 motor back in the late '90's - Autofarm in the UK.

If the Type M96 plague hasn't struck you, you're probably more likely to side with Brian PT.

But, if you're the proud owner of an alloy boat anchor manufactured in Stuttgart, you're likely to remain somewhat more skeptical.

[clickman]

^^^ Trust LB to burst my bubble.