[potato1337]

Some time ago I started noticing weird behavior in my M2 competition DCT. When the car was rolling (without touching a throttle), and then giving a decent amount of gas (less than required to break traction) sometimes you'd feel a "double push" in the back from the acceleration. It felt like there was something "loose"/with play in the drivetrain.

I suspected something was off and reported it to BMW. I was informed after a test drive with a tech that it was "normal" - the car is DCT and when off the throttle it was disengaging clutches and when pressing the throttle it was engaging them, that's why I could feel "double push". Didn't buy it, I was 100% sure it wasn't like that before (the car was at ~55kkm) and insisted they check it on the lift. They found the transmission mount was starting to break and that if I wanted they could replace it under warranty. I agreed and after the repair, I couldn't reproduce the "double push" again.

They also said that there was very little play in the axle shafts but nothing out of spec that should be addressed. I was happy that I no longer felt the "double push" and didn't pursue this.

I feel like something is loose/there is more play now (now at 60kkm and warranty about to expire) and gonna take it to BMW but wanted to ask a few questions, fellow forum users:
1. Is the statement about "little play in the axle shafts is normal" true or have I been bamboozled?
2. When the car is on even ground, switched off in gear, and no handbrake engaged when pulling/pushing the car forward/backward it moves a little and at the "edge" it makes a clinking noise. Managed to capture it on

View post on imgur.com

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3. Same conditions as in 2 but the single rear wheel in the air, when trying to rotate it, it rotates a little and at the max of the rotation, I can hear very similar noise as in 2. Is that normal?
4. Any suggestions on what else should I make them look at before the warranty expires?

[c0riolis]

Originally Posted by potato1337

the car is DCT and when off the throttle it was disengaging clutches and when pressing the throttle it was engaging them, that's why I could feel "double push"

This is 100% BS, the clutches are engaged whenever you are in gear.

Do you feel/hear knocking on the rear axle during load reversals (step on the throttle, let off, step on the throttle again?

If yes, it could be your differential bushings, or (like it was the case for me), some of the driveshaft bolts coming loose.

[inTgr8r]

Originally Posted by c0riolis

This is 100% BS, the clutches are engaged whenever you are in gear.

Do you feel/hear knocking on the rear axle during load reversals (step on the throttle, let off, step on the throttle again?

If yes, it could be your differential bushings, or (like it was the case for me), some of the driveshaft bolts coming loose.

Try stopping on a hill and then let your foot off of the brake. (& no throttle)
After the hill hold releases the brakes the car will roll freely.

[c0riolis]

Originally Posted by inTgr8r

Try stopping on a hill and then let your foot off of the brake. (& no throttle)
After the hill hold releases the brakes the car will roll freely.

This is true, the clutches are disengaged when you stop, but the OP mentioned that he was already rolling forward so I assumed that his clutch was already engaged when taking his foot off the throttle.

I should have said the opposite: the clutch is never disengaged unless you stop or force the car to neutral by holding the gear selector in the left position.

[potato1337]

Originally Posted by c0riolis

This is 100% BS, the clutches are engaged whenever you are in gear.

Originally Posted by c0riolis

I should have said the opposite: the clutch is never disengaged unless you stop or force the car to neutral by holding the gear selector in the left position.

Yeah, DCT is pretty noisy and you can actually hear the clutch disengage when putting the gearbox into neutral when rolling (by moving the gear selector to the left) or when coming to a complete stop. It doesn't happen when rolling and lifting off the throttle. That's why I didn't buy this "clutches get partially disengaged when off the throttle" bullshit.

What do you think about the noise from questions 2 and 3? Does that seem normal or out of order?