[PhaseP]

Used to have a Miata NB, the year model I had was infamous for clutch shudder at take off. The problem was flywheel surface material and clutch material wasn't very compatible. Factory solution for later years was using different clutch material. I never replaced the clutch though, had gotten used to. Overall with Miata it was always after a damp and cold day in the morning first few take offs it was doing the shudder. I think material transferred from clutch on the flywheel was rusting during damp nights. Then a bit of slipping at take off was getting the surface cleaned off.

With my E90 after 12 years 120K miles, I only experienced this judder two time this winter recently. I chuck it up to the 330 flash I did (Thanks Hassmachine!!). Because after that long driving the car, now I am not used to the low end torque increase. It takes different amount of gas modulation, actually less of it .
I do love the flash upgrade, 40 more horses!! (on paper spec US 325 vs US 330, 215HP vs 255HP)

[hassmaschine]

I think it could very well be lugging it that causes it. Because if I drive a lot in slow traffic, I'll notice it, but if I'm on the highway a bit more (and taking off faster, beating a bit on the clutch) I never notice it. And I'm much more likely to lug it around if it's cold/damp than when it's warm and dry.

[wrongmark]

It does seem worse in stop start traffic, which is most of my day to day driving. I have tried slipping the clutch while moving for 30 seconds or so to supposedly 'clean' the surfaces of the clutch/flywheel. It did seem to work a little, no doubt at the expense of some extra clutch wear. I suppose I'll just put up with it until the clutch fails and then make sure the DMF is replaced at the same time.

I suspect my DMF has more play in it than it should because the car shakes like crazy when it does judder.

[Terraphantm]

Originally Posted by wrongmark

It does seem worse in stop start traffic, which is most of my day to day driving. I have tried slipping the clutch while moving for 30 seconds or so to supposedly 'clean' the surfaces of the clutch/flywheel. It did seem to work a little, no doubt at the expense of some extra clutch wear. I suppose I'll just put up with it until the clutch fails and then make sure the DMF is replaced at the same time.

I suspect my DMF has more play in it than it should because the car shakes like crazy when it does judder.

I’d be willing to bet it’s throwout bearing for you. Mine started off similarly - occasional judder when getting started for years, somewhat worse in traffic. Then this summer it became judder on every start. Then judder on shifts into higher gears. Then it started making this noise whenever I depressed the clutch:

At that point I stopped driving the car until I had a chance to pull the transmission. Found this:

[wrongmark]

Whatever it is, I guess it'll have to wait until the clutch fails before I start throwing money at it, at which point I'll have all the surrounding "consumables" replaced at the same time incl. DMF.

[Terraphantm]

Originally Posted by wrongmark

Whatever it is, I guess it'll have to wait until the clutch fails before I start throwing money at it, at which point I'll have all the surrounding "consumables" replaced at the same time incl. DMF.

Yeah I would say when the problem becomes an every shift type of thing, you should start planning on an overhaul. And if it starts rejecting gears on you, then park the car until you can work on it

[fleetfoot]

I've had numerous issues with clutch juddering over the years, especially when cold. I bought my car new in 2013, and the dealer replaced the clutch under warranty at around 30,000 miles when it started juddering. Now I'm at 112,000 miles and it's juddering again. I tried flushing the clutch fluid today, and that seems to have fixed it!

Flushing clutch fluid can go wrong due to the ease of the small clutch fluid reservoir in the larger brake fluid reservoir going dry. When that happens, you push air into the clutch system, and it sounds like a major pain to bleed it out.

This is the process that was successful for me:

1. Fill brake fluid reservoir to max
   
2. Fill catch can with ~1" of fluid (to prevent air from backflowing)
   
3. Fill pressure bleeder, and pressurize bleeder to 18psi
   
4. Remove transmission belly pan (3 8mm screws in front, 2 in back, and 2 on each side).
   
5. Remove cap from bleeder valve on slave cylinder, attach catch can hose, and loosen it one (maybe 2) full turns with an 11mm box wrench.
   
6. Let fluid drip until you see fresh fluid coming through
   
7. Close bleeder valve. DO NOT apply too much force since it's PLASTIC. Put rubber cap back on.
   
8. Reinstall belly pan and you're done.

A few thoughts:
The fluid flowed right through for me, and I had zero issues with air bubbles. I did check numerous times that the brake fluid and power bleeder reservoirs were full. I also tapped the brake fluid reservoir quite a bit to get air bubbles out.

I didn't have any issues getting to the bleeder valve on the side of the transmission with an 11mm box wrench.

I suspect that the flushing method of pressing the clutch pedal (especially multiple times) just moves too much fluid too fast, and that might be why the reservoir gets drained leading to air bubbles. IMO power bleeding is the simplest and safest approach. I did the whole thing in less than 15 minutes.

[DaanBMW]

mine judders since I got it, in 2011 w/ 66k miles. summer, winter, mostly slow driving (like parking in garage slowly to not hit the steel pole in front of the furnace). not always, and like OP says never could figure out a real pattern to it. I only drove manual all my life, this is the car only car that judders. also it's not the DMF, I replaced the clutch - exactly bc of this issue!! - with a Valeo SMF and guess what - it still does it.

now at 150k+ miles and it's getting neither better nor worse. another bimmer weak point, like the shameful Getrag gearbox

[Runnin'Rich]

Mine has never juddered.
At 140k miles:
While sitting in the drive through with the window down I could hear the sound of the worn throw out bearing reflecting off the brick wall. A whirring which changed when I pushed the clutch pedal in.

The DMF was slapping slightly back and forth if I would stab the gas pedal in 1st or quickly lift off the pedal.

I had even wear on the original flywheel when I removed it. The DMF had some play but the spring back was not far off the new one.

After replacing DMF clutch and all the ‘while your in there’ parts, it all worked a lot better the bearing noise was gone. The ‘looseness’ when stabbing the throttle was reduced. This made it slightly easier to perfect gear changes, something that I’ve found had not come naturally on this car.

Changing to the Ultimate Clutch pedal helped the most, and even I think 3SIM maf less(thank you hass) has helped with throttle pedal delay.
I think the biggest weakness is that I can’t feel the bite point through the clutch pedal. Maybe it’s because I’m previously used to cable operated clutch pedals with way more feel.

Changing the dmf didn’t fix the slapping sound on engine shut down with clutch pedal out. My e36 never did this and I’m surprised this would make it through BMW quality control to be ‘normal behaviour’

[PhaseP]

Originally Posted by Runnin'Rich

I think the biggest weakness is that I can’t feel the bite point through the clutch pedal

Do you still have the clutch delay valve? When I had removed (the internals of that valve), this was the only improvement I had noticed. The bite point was always vague before, it became more defined after removal. It is very slight improvement though.

A warning seeing you are from Canada, if not already removed/replaced the clutch delay valve, it will most probably stuck in place with corrosion. It is plastic but goes into a metal part, metal part grows corrosion making it stuck. At the least its o-ring will not come out unscathed. The locking clip on the part it goes into will have turned to rust and etc. That is how mine was years ago when I had removed the restricting element from inside the clutch delay valve. Although later year builds than mine had gotten plastic clutch slave cylinder, and the connections may have been less prone to corrosion, don't know.

[Runnin'Rich]

I’m on the west of canda so no salt on the roads luckily.
You’re right CDV removal made a little bit of an improvement but it’s still vague compared to other cable throttle cars I’ve owned.
UCP was the biggest gain although if you’re size US13/14 shoe your toe will rub the arm above the pad because there is way less of a curve in the arm of pedal

[wrongmark]

Just a little update: I'm still on the same clutch at probably 110k miles. Although I have replaced the brake fluid mutlple times in my ownership, I've never bothered to flush the fluid at the clutch cylinder. Decided to do it this time (need to top the resevoir to the brim and then used a pressure bleeder) and it has made a difference. I still get a slight judder occasionally. Maybe it's just taken the spongey-ness out of the clutch pedal making it more controllable?

I toyed with removing the CDV while I was crawling around but couldn't be arsed in the end.

[DaanBMW]

Originally Posted by wrongmark

Just a little update: I'm still on the same clutch at probably 110k miles. Although I have replaced the brake fluid mutlple times in my ownership, I've never bothered to flush the fluid at the clutch cylinder. Decided to do it this time (need to top the resevoir to the brim and then used a pressure bleeder) and it has made a difference. I still get a slight judder occasionally. Maybe it's just taken the spongey-ness out of the clutch pedal making it more controllable?

I toyed with removing the CDV while I was crawling around but couldn't be arsed in the end.

my experience with this - in a month the symptoms will be as they were before the fluid chg.