2017 M6 complete power loss

[jaf30]

I have a weird issue where occasionally my M6 completely loses power for 2-4 seconds before recovering. It feels like the car has jumped out of gear.

This only seems to occur when accelerating off a roundabout. It just so happens that it's the same roundabout every time, but this is likely a coincidence.

Things I've noticed when this happens:

• After leaving roundabout, starting to accelerate to near wide open throttle.
• Every time I've checked, the car has been in 3rd gear at about 3,500-4,000 RPM.
• Engine holds its revs during the power loss.
• Not traction control - no light on dash to suggest this.
• No error codes in ISTA whatsoever.

Other than this one occasional issue, the car runs perfectly - No rough idle, smooth power delivery throughout the rev range. My current thoughts are that a clutch may be on its way out.

Not sure if anyone else has had a similar experience who could shine some light on this?

Car is at 71k miles. Fully up-to-date with servicing.

Thanks

[MeesterQ]

When is the last time you replaced your transmission fluid?

[jaf30]

Only (somewhat) recently taken ownership of the car, I don't think it's ever been changed so it's definitely on the priority list. I'll probably change it during the Xmas holiday period.

Is this a symptom of bad fluid?

[MeesterQ]

I believe so.
I changed my trans fluid out at 25k miles.
Also would recommend taking a look at the clutch if a simple fluid swap doesn’t fix things.
Also check your diff fluid or change that out at the same time.

[Cincinnatus]

Is it possibly the DSC kicking in too hard?

[KurtsM5]

Turn off DSC, turn on MDM, see if it gbreaks the tires loose(be careful!!!) If so, then Cincinnatus is right. DSC is preventing tire spin.

[jaf30]

Presumably if it was DSC I'd get the flashing light in the instrument cluster?

I now have the service parts for the DCT, but still wating on the new oil to arrive.

Thanks