997 C4S new clutch still judders

[smartone]

Hi, I would be extremely appreciative of some help. My carefully driven but second hand 2005 997 went through a clutch last month, after a total of 39,000 miles. Whilst replacing the clutch I was advised that the dual mass flywheel was in poor condition, oil was leaking from rear main oil seal, intermediate shaft seal and oil leak from gearbox output shaft. I therefore had all oil seals replaced and the bearing, and bolts. Previously, I had long experienced a noticeable judder from standing start and assumed upon eventually changing the clutch that this would go.....it hasn't and the garage (not Porsche) are confused as to what may cause it. They don't want "me" to incur significant costs without knowing what the problem may be. They've suggested engine mounts and the gearbox. They've told me to drive it hard as sometimes it can be caused by the 4WD not kicking in when driven very carefully and as a result, it may be this.

I am sure that I can 'feel' the clutch engaging, through my left leg, when driving along, although this judder is most pronounced only at standing start with low revs.
Anyone have any thoughts....the garage said that it would be highly unlikely that the new clutch and parts were at fault.
Cheers

[SEE YA]

Maybe take it to another garage to see what they think?

[Actus Reus]

Presumably the flywheel was changed?

[smartone]

Flywheel was indeed changed yes!

[MadMark911]

Get a second opinion! It only takes them not having fitted a seal correctly for you to be needing a new clutch - again!

[Ian_UK1]

I'd ask your garage to carefully check the condition of the engine and gearbox mounts as well as reviewing their clutch installation. If either/both are in less than perfect condition, they can give rise to what can feel like clutch judder (but is in fact the whole engine/gearbox assembly juddering). The big, single gearbox mounting bush at the forward end of the gearbox is the most likely to cause these symptoms.

[anonymous-user]

Unusual for mounts to be shot in a car that young. Judder - particularly in reverse - can be due to diff issues too, although I am not familiar with the set up on a C4s. Very common on GT3s with LSDs.

[smartone]

Thank you for the replies to date...
@Ian_UK, that makes sense because I am convinced that the judder is NOT just when I pull away, but it's very much more difficult to notice when driving and changing gear normally.....the car suspension is pretty hard anyway, so the slightest of judders when lifting off the clutch pedal is almost impossible for me to know if its in my head or not....it's almost not a judder as such but I am sure that I can feel something through my left leg in addition to the standing start judder. I am sure that its more than just the clutch ....so the gear box bush comments make a lot of sense.
I will have a second opinion for sure, maybe this time a P specialist....
thanks again, I will be back when I know more.

[smartone]

PROBLEM SOLVED

It was the master slave unit that was 'broken'...quick simple to fix....when removed I could push the piston arm in and could feel the judder or it felt like it was sticking or there was no fluid inside, so it was as if it had lost its smoothness.

[marccon]

Hi Smartone,

My car has a very similar issue.

New Clutch, kit, flywheel, bolts, gearbox seals, engine mounts, rear drop links

Fitted by a very reputable independent specialist.

When I release the clutch in first without any throttle there's no shudder

If I give it slight throttle, I get a shudder until the clutch is fully released

If I give it more throttle, I cant feel the shudder (unsure if the increased revolution is masking the shudder)

Had it back in twice on the last occasion (three days ago) specialist loosened the engine mounts and gearbox to I think reposition them. On driving still have a shudder but its not as bad.

Do you think a Slave Cylinder change is the answer, would there be any signs apart from the shudder to look for??

Mark

[smartoneha]

Hi Mark
Sorry I was on holiday when you messaged.

I'm surprised that the slave cylinder wasn't done with the rest as it will involve dropping the engine etc...and removing the clutch again. There is a part of it that wears so this maybe the problem. I'm not the expert but it improved things for me.

I also took mine to Porsche after my local guy did it, and they said that the clutch was well within their tolerance limits. So even if they'd done the work themselves, it would be have been deemed fine!

I kind of wonder whether it's normal for some clutch judder on the manual cars, but again, I'm not the expert.
PS I sold mine in the end to buy a new Range Rover 4.4 V8, yes that's a swear word, but I've no clutch judder now!!!!

[smartoneha]

Marccon,

Forgot to say that mine really was bad before the slave cylinder was replaced. In fact the problem was two fold, a judder plus more of a loud creaking noise when I let the clutch out. It was like opening a door with rusty hinges. When the SC was replaced, the judder was still there but it was better.

I'd add a cautionary note here to say that if you have absolutely no creaking noise when engaging or disengaging the clutch, the Slave may not be the problem......I'd be interested to hear how you progress.

Simon