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6MT folks- Anyone experience this after spirited driving?

Update: got the car back today. It’s vastly improved but the shudder isn’t completely absent as it was prior. They said there was an ECM update for “updated calibration for improved knock response” and after they did that, the tech and shop foreman both noticed the improvement as well. They also opened a case for GM to look into it and after dealer sent over some logs, they determined everything is within normal operating parameters.
 
Not sure how clutch shudder and knock sensors could be related. Knock sensors pull back timing due to bad gas or lower octane. That usually happens a higher speed and rpm, with clutch fully engaged. In my experience clutch shudder is usually due to uneven pad deposits on the flywheel or a dual mass friction plate shedding material and getting unbalanced
 
Drove it this am and albeit reduced, it’s still there. More noticeable when everything is cold. GM likely didn’t authorize dealer to dig in further- at least for now. I’m going to live with it for a while and if still bothersome, I’ll escalate it. It’s been my hunch as well that it’s clutch/flywheel/engagement point related and as some of you noted a throw out bearing or things @DCV mentioned make sense to me.
 
OP your description of the issue has all the hallmarks of a warped flywheel. Or one that has deposits on it that are causing the shudder. It is generally most noticeable when cold. Slipping the clutch a little too much when hard launching can cause this.
 
Might need a new flywheel and friction plate or get the one that’s in it turned. If that’s possible, in the so called old days one could get a machine shop to lightly turn the surface of a flywheel. Now? Probably not, plus it takes the right machine and skill set.
 
Might need a new flywheel and friction plate or get the one that’s in it turned. If that’s possible, in the so called old days one could get a machine shop to lightly turn the surface of a flywheel. Now? Probably not, plus it takes the right machine and skill set.
I might be wrong, but I don't think you can do that with a dual-mass flywheel. Believe I read that from way back in my E39 M5 days.
 
Your correct. Not sure if the BW has dual mass flywheel. Also the clutch is considered a wear item, and generally not covered under warranty. So the OP may have to do the old “I’ll take it apart and if I find the flywheel was defective the warranty will pay for it, if it looks like wear then you’re going to cover the cost of taking it apart, install new flywheel and clutch and reassemble” by the dealer. Tranny has to drop and probably the exhaust and drive shaft to do this type of job
 

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