[hefdog]

We have a 2007 M5. Miles are at 42,000. Those are not hard miles, just local road and freeway driving here and there. We do not pounce on this car, it's just not worth getting a ticket to do it. We bought it new and plan on keeping it.

We've had no major repairs, only normal maintenance work. Over the course of the past 4 years we have noticed that the transmission seemed "sloppy," meaning an occasional subtle "klunk" between shifts, mostly when crawling and accelerating slowly in traffic. We've pointed this out to BMW every time it went in for service and they would always say there was no problem. In the past few weeks we could also feel a subtle shutter upon acceleration from a stop, and very faint squeal (like brake pad noise) in a slow crawl. That symptom would come and go, and BMW did not find a problem the last time it was in for other routine maintenance.

Today is the last day for both the BMW Maintenance and Repair Warranties. We have a 3rd party repair warranty that takes over from here, and the maintenance is on us from now on......The plan is to have a local reputable BMW shop do my repairs from here on out.

So, on this, the last day of maintenance/repair warranty for scheduled service (oil/filter), we mentioned again about the transmission "klunk," acceleration shutter, and brake noise just to make sure it was documented before going out of warranty. Lo and behold, the service adviser called a few hours later and said that the clutch is bad and BMW corporate agreed to replace it under warranty.

We feel fortunate this was caught now. The adviser said the technician noticed the "klunk" and immediately diagnosed it as a clutch. The car accelerated and the SMG system worked fine. We find it a bit of a reach that a "klunk" in the gears is a clutch problem. However, my concern is that a clutch could go out with only 42K miles. We are not hard drivers, and mostly drive the car in automatic. We are also am a bit leery about the workmanship at BMW with this, they seem to move so many cars in and out of their service bays that we wonder if they really pay attention to detail there.

How serious is a clutch going out at 42K miles from "normal" non-abusive driving? Based on the symptoms described above, does this sound like a clutch? Is there maybe something more? And why didn't BMW act on this before when we mentioned it over so many service visits, but then act on it on the last day of the warranty??? Very strange...... Since we am out of warranty after this repair is done, will BMW stand behind the repair? In other words, is the work they do on this repair under any kind of warranty?

Thanks for your help.

 

[bnewton]

If you read some other threads on the clutch you will find that many members have had issues at low miles. Some have been through 2 clutches by the time they hit 42K. There has been quite a bit of discussion regarding the reasons for premature wear. One theory I came across is that easy driving causes higher clutch slippage and can actually accelerate the wear. This is due to the car sensing (based on the rate of change of throttle position) that you aren't trying to take off quickly and will engage the clutch in a more "civilized" manner, rather than just dropping it for max acceleration. I don't know too much about the topic but if you pay attention to what the clutch is doing and how the feel changes based on your use of the throttle, this theory is plausible in my mind. These are high performance cars and are meant to be driven hard. They have a clutch that supports that use.

 

[CSBM5]

Numerous threads here point to the throwout bearing galling on the guide bush sleeve it rides on. People have pulled transmissions only to find the actual "clutch" (i.e. the flywheel, pressure plate and clutch disc) are all fine, but the whole "bang in the back" and unruly SMG behavior was due to the throwout bearing hanging up on the guide bush. Of course while it's all apart, you go ahead and replace the clutch disc, pp, etc, but they weren't the cause in those cases of the issue.

Note that driving it hard or not would seem to be irrelevant to the t/o bearing galling issue. In fact, the more time the car has spent in traffic (i.e. the duty cycle of the t/o bearing is VERY high on the SMG since it is always "managing" the clutch for you in those conditions), etc, the more likely you'll experience the t/o bearing issue. Lots of highway driving sees virtually no t/o bearing use. Hence it's easy to imagine a car with 70k miles having a better shape t/o bearing than one that has done 30k miles of city driving.

Chuck

 

[ideliver]

Numerous threads here point to the throwout bearing galling on the guide bush sleeve it rides on. People have pulled transmissions only to find the actual "clutch" (i.e. the flywheel, pressure plate and clutch disc) are all fine, but the whole "bang in the back" and unruly SMG behavior was due to the throwout bearing hanging up on the guide bush. Of course while it's all apart, you go ahead and replace the clutch disc, pp, etc, but they weren't the cause in those cases of the issue.

Note that driving it hard or not would seem to be irrelevant to the t/o bearing galling issue. In fact, the more time the car has spent in traffic (i.e. the duty cycle of the t/o bearing is VERY high on the SMG since it is always "managing" the clutch for you in those conditions), etc, the more likely you'll experience the t/o bearing issue. Lots of highway driving sees virtually no t/o bearing use. Hence it's easy to imagine a car with 70k miles having a better shape t/o bearing than one that has done 30k miles of city driving.

Chuck

great post....

 

[w8m5]

Don't forget to do the SMG reset every 3000 miles or so, when changing tires, or whenever it gets too klunky,

 

[ecain63]

I asked this question on PH the other day. Im not convinced that these cars need clutch replacments as early as we are advised. And why on earth would we need a new flywheel? Have you seen the size of them?

In my 10 years of driving ive never heard of a flywheel lasting less than 100k - 150k, let alone 30k. Most of my old cars had been through 4 or 5 clutches before there was any sign of wear on the fly. The M5 fly is huge, and looks much the same as an anti-tank mine. Given the low levels of torque produced by these engines its hard to see how they get worn so quickly / at all.

As for the clutches. They are made by Sachs which is a very good company and as far as im aware they are carbon plate clutches that should in theory last longer than the car its fitted in. So why are they only lasting 30k to 40k? As i said above, this is a low torque engine after all.

Also, if the SMG computer is so good at making gear changes then shouldnt this reduce the wear on the system right down to a minimum?

As has been mentioned before, maybe its never the clutch that the issue. Maybe our problems are with the throwout / release bearing. We know they dry out and start to stick and this is often the cause of the gauling / dragging we get. The dragging would explanin the 'juddering' on take off and the galling would possibly explain the 'klunk' you sometimes get.

As for the theory that we should do the clutch and flywheel when the box is out because it'll save us money / time later, im not convinced. The good book says that a clutch change only takes 4.5 hours. 90 minutes to drop the box, 90 mins to change the bits and then another 90 mins to lift the box. Thats about £600 at a UK dealer or £350 at a good indy which isnt really that much in the scheme of things (work out US rates as per your own experiences). Parts alone are £1750 to £2000, including the flywheel, clutch pack and bearing so you can see where the costs are. The bearing is only £80 to £100 and in my opinion that should be the first port of call rather than emptying your wallet for a clutch and fly you might not actually need. So changing the clutch because the box is already out of the car isnt actually a money saving tip unless the clutch is actually worn out. And then, if the clutch is worn, do we actually know if the fly is worn? Im not convinced that we arent being done over by the dealers just so they can claim the warranty money or labour charges.

I might be wrong and i'll probably be told so but i'll need to be convinced im wrong about the issue of clutch / fly wear before i change my opinion. Its a bloody pricey job and i want to make sure its actually neccessary before i part with my £2000 to £2500.

Also, has anyone actually seen their clutch after its been replaced? Any pics?

 

[allmotor_2000]

I saw my clutch during the replacement (unfortunateley did not snap a picture). There are two discs - one on top is easy to handle
while the other is built-in with the pressure-plate assembly. The flywheel in my case was perfectly fine so unless there is abuse or
REAL hard driving, it should be fine for 100K. My clutch showed about 70% wear at 43K miles, so probably 50K is the life under normal
driving with the occasional bursts - I don't use LC at all.

I expect the new clutch to last at least another 40K. The bite, shifting etc. are much smoother and better although I would attribute
the latter to SMG reset and 'teaching' the clutch. Since there is no manual clutch, there is a CPS (clutch position sensor) that engages
the bite-point and knows exactly where the full engage, bite-points etc. is. This I believe is critical to wear since the wrong bite-point
can have the effect of riding the clutch in a fully manual tranny car.

 

[hefdog]

Can somebody explain more what "resetting the SMG" means. It sounds like a longer throw-out bearing and clutch life can be achieved by doing that, perhaps avoiding a $3500 TO bearing replacement job every 40K miles!

In my older cars, I used to get 100K miles or more out of my clutches and TO bearings by correct usage of the clutch in stop and go traffic and not drag racing the car every time I drove it. It's all in the habits used to drive the car.

As an update to my repair at BMW: The dealer is in the process of replacing my clutch, flywheel, and TO bearing. I called them and asked for a diagnosis as to what part actually was worn while it was still on the hoist. They confessed that the TO bearing was the culprit. They also said it was BMW's policy to replace the clutch and flywheel when a bad TO bearing is detected. I got the impression from the serviced adviser that there was plenty of life still left on the clutch and flywheel but they replaced it anyway since those parts come out in the repair to get to the TO bearing. BMW has made it a policy to replace all three parts at the same time.

It also sounds like the TO bearing in this car is a design flaw.

The BMW people there at the dealer really don't know squat about the M5's. They only say "drive the car hard, they are designed that way........the car demands that you abuse it. If you baby the car it will break down." I never got a clear-cut answer in the 4 years I've owned this car from BMW as to the logic behind that thinking. That is total BS in my opinion. Does BMW think we all lead a James Bond lifestyle out there? That is an unreasonable expectation on the part of BMW to be promoting that type of driving. In the United States, especially in urban locations, if you try to drive these cars hard and at excessive speeds you will be hung by local police. Let's be real BMW.

BMW (at least in the US) needs to give accurate information to guide their M5 car buyers how to economically drive these cars so they last, not so that they break and fall apart or so that we end up with hundreds of speeding tickets and being dropped by our insurance carriers. This isn't Germany for God's sake. To have a TO bearing fail because I am not driving the car hard and fast on extended highway miles is an expectation that isn't always possible here. We are confined to local street (stop and go) driving and occasional freeway driving where speeds over 65mph usually result in a ticket.

In traditional manual transmission cars with clutch pedals you are taught to conserve the clutch and TO bearing in stop/go traffic by not keeping the clutch engaged while sitting still. I taught my kids that technique when they were learning to drive since all my cars then were clunkers with manual transmissions. But apparently with this M5, "riding the clutch" is still possible even though there is no clutch pedal to help save the TO bearing. What options are available to us M5 owners for getting longer life out of the TO bearings (and the clutches) in these cars? If resetting the SMG is the answer, then why isn't BMW and the manual itself giving that advice??? Why isn't that common knowledge by BMW dealers and shops?

I realize I bought a unique car with lots of power and speed capabilities and with high-tech qualities. I like having the power when I need it to pass or get onto the highway safely. But I also want information to help me keep the car from frequent repairs within the context of the limitations I have and the urban driving conditions I'm stuck with. If these cars are meant to be driven hard to last, then they should only be sold in Germany and not imported here.

 

[CSBM5]

I would hope it goes without saying to your dealer, but make sure they are replacing the guide bush, #1 in this pic also. Do not let that transmission go back in the car without a new part (it's cheap) no matter how good they say it "looks". I would hope by now that BMW forces dealers to replace this part each time, but you never know.

As to the other questions, I think the SMG simply has the clutch disengaged huge quantities of time in daily driving, especially city driving. I don't think it ever puts itself in neutral, so the throwout bearing gets a ton of usage compared to a typical manual with an educated driver like you mentioned. It appears to be a design flaw in the sense that they miss calculated the wear it would experience...the one thing that stands out though is the galling against the guide bush as that appears to be an outright design issue. Over the years whenever I've had a bad t/o bearing, it was the actual bearings/race that were worn, but on the SMG it appears to be this galling issue against the guide bush often. ??????

 

[ideliver]

personally....i keep my car in N when stopped....just like a conventional manual...

 

[w8m5]

Resetting the SMG is a procedure, defined in the manual, to cause the SMG to adjust itself to clutch wear and tire size, etc.
To do it, drive at lease 40 mph, shift into neutral, hold back both paddle shifters for 6 seconds. That's it.

 

[w8m5]

Also, it has been discussed here a lot, but I believe the problem here is a manufacturing defect. The TO bearing was not lubricated correctly when installed, causing it to bind.

 

[M Mode]

Has anyone had the clutch disc break (SMG version)? How many miles on the car? I was told the center tore away from the disc on my car. This happened at over 80,000 miles. They replaced the clutch, disc and flywheel. I have a BMW extended maintenance which states the clutch is covered due to normal wear and tear. Initially the service person said it was covered. However over a month later they called and said BMW NA declined to cover it. Has anyone dealt with a clutch replacement under the extended maintenance agreement and had it covered?

 

[ideliver]

Initially the service person said it was covered. However over a month later they called and said BMW NA declined to cover it. Has anyone dealt with a clutch replacement under the extended maintenance agreement and had it covered?

What was their rational for refusal??? A defective part hmmm??

Clutch is explicitly covered as part of the extended mainenance....BMW North America

 

[M Mode]

What was their rational for refusal??? A defective part hmmm??

Clutch is explicitly covered as part of the extended mainenance....BMW North America

Their main theme is that the clutch is covered for "normal wear and tear" only. That is one reason why I am curious to know when other’s clutches have failed or simply broke. Another statement made by BMW is that the disc needed to be worn to a certain level vs. the rivets - although nothing is mentioned in my extended maintenance warrantee about the wear spec. They said since the clutch "broke" and was not "worn" to the spec level it wasn’t covered. What I asked and didn’t get an answer to is roughly at what mileage do clutches on the SMG fail due to “normal wear and tear”. I was told they don’t have enough M5’s with my mileage - >80k.<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com<img src=" /><o></o>

What the “BMW Maintenance Program Upgrade Agreement” does say is: “In addition, the replacement of THE FOLLOWING ITEMS ONLY due to normal wear and tear are also covered: Brake linings (pads) and rotors (both covered only when worn below limits as per BMW Technical Data Information); external drive belts; clutch; . . . . . .”<o></o>