I’ve trawled the internet for many years now reading about this issue, its causes and possible miracle fixes. I won't bore you with my limited physics and stroboscope knowledge (we have Ade for that)
but have a reasonable understanding why it happens. I believe it's all to do with resonance interference and frequency of the engine in relation to the transmission causing harmonious interference (clutch judder) in certain situations. However, there are two causes of ‘clutch judder’. Here's my personal account and understanding of both types and the latest information I know of to date.Not long after I bought the car, I started to experience the clutch slipping (juddering) first thing on the odd morning when certain environmental parameters occurred. Usually when the temperature was fairly low, mildly damp atmospheric conditions and a cold engine. The car had only covered 19687 miles. After reading up on the possible causes, I got the car booked into Sytner Sheffield for them to take a look (July 2009). As the car was just out of warranty (Alpina only covered by 2 a year warranty) I was very much at the mercy of BMW/Sytner as to who would pay for this to be fixed.
I agreed for this to be investigated (at my cost) and the clutch/gearbox stripped down. As suspected from my research, the diagnosis confirmed a faulty seal on the dual mass flywheel (DMF) which allowed fluid to seep onto the clutch plate and cause slippage until it burnt off after the first couple of starts. As this was a known fault, I had the clutch and flywheel assembly supplied and paid for as goodwill from BMW. Sytners footed half the bill for labour so I paid a substantially smaller fee for the work and as I’d contributed towards the work, was still covered by the parts warranty. I recall when I collected the car, I asked if it was a permanent fix or would it happen again. I was told (off the record) that cars had been known to re-visit several times for clutch replacement (this didn’t really fill me with much confidence but was appreciative of the honesty). I couldn’t fault Sytners and their service was first class.
The clutch operation felt perfect for a couple of weeks, like a new car. A joy to drive but the dreaded judder soon returned. However, this time it was more sporadic and would happen at different times, not first thing on a morning when the engine was cold. Now it would happen especially when starting to move off an incline in 1st or reverse gear, particularly violent at times.
Further reading into this, I soon came across many instances of this occurring not only in BMW/Alpina cars but over a broad range of manufacturers and vehicles. The common theme was the DMF. Why was such a poor design allowed to occur and be so common through so many differing vehicles/manufacturers. I initially thought and read that it was only a problem on the 4 pot diesels but have heard a few examples on the 6-ers too, although I haven’t read many cases and this may be the oil seal issue on the dual mass flywheel (as per my original clutch issue).
Over the last 7+ years, BMW released several 'software fixes' which basically raised the revs when engaging first or reverse gear which just made you ride the clutch more (and burn the clutch worse) and made it sound like you had terrible clutch control. I'd refused to get the software fix applied to the car as I always knew it was a mechanical fault and this was just a mask of the real issue. I believe this has been an issue since the later E46 models with the M47 engine.
I'd read elsewhere (E90 forum) of a new clutch assembly BMW have been developing and released earlier this year (2012) which is meant to totally eliminate the clutch judder issue. In February this year, BMW launched a new clutch assembly which finally seemed to have eliminated the fault from reading experiences from people who’ve had it fitted. Great! I thought, finally a permanent fix to this annoyance, where do I sign up!
Over the last couple of weeks I’ve been speaking to Sytners again about the ongoing issue. Although a well documented problem on internet forums, there is a bit of a hush hush approach from BMW (and presume other manufacturers) on this. BMW would never do an official recall, it would cost them millions!
From my discussions with Sytner (Sheffield) about the problem I have been told the following:
The new clutch assembly is only available on cars fitted with the N47 engine (later model)
The D3 MT has the older M47 engine of which there is and planned to be no revised clutch assembly produced.
Sytners have, as ever been very helpful in looking into the possibilities and options I have but this basically means either living with the occasional frustration of dealing with the judder when it occurs, or shelling out and getting the clutch replaced at a cost each time (indefinitely). I’d expect BMW may provide another clutch assembly FOC but it’s a lottery as to whether this would fix the issue, it’d last as long/short before reoccurring or return worse than before.
As it is a very occasional problem on my car I’m tempted to say live with it and be glad it’s not worse. However, when it does occur, the whole driving experience of what is a wonderful car is overshadowed by an inherent design fault which BMW don’t seem to want to address.
I’ll see what options Sytner come back to me with and take a commercial view to see if it’s worth the expense.
So some good news if you’re running the N47 engine, not so good for the M47 owners.
Again, sorry for the long post but this may be useful to someone if not a record for myself (and get it off my chest)
P.S - Nearly forgot to add as it's often linked when reading about this issue. Removing the clutch delay valve makes no difference to this problem, trust me.
Now that was bad enough, but trying to restart a stalled push-button stop/start car takes a bit of thinking about (gotta love key-operated ignitions) and it took me 10-15 seconds more to get her going and pull away (juddering as she went) with the bus driver now giving me the well-known hand gesture rhyming with banker. Now if I'd stalled across the lane and he'd been still moving after calling me out......may have been very embarrassing. So, what I'm saying is that in essence there is also a safety issue with this problem.
