535d E60 272hp ZF 6hp26x weird tapping sound

[MielsenW]

Hello first of all, I would like to apologize for writing directly to the BMW forum but you can probably only advise me here and I'm getting desperate
Can someone help me track this sound? I have M57 535d 272 hp + ZF6hp26x from E60 swaped in Nissan Patrol.

A couple of months (4) after the rebuild, this knocking sound started. It only sounds when the car is cold and under light load. There is no sound in neutral or at idle. When revved up to speed, it doesn't either. At full throttle under load also no sound. The inverter is 4 months after refurbishment.

Otherwise, the gearbox shifts perfectly normally and you can hardly even tell that it is changing gears.

Thank you

[MielsenW]

I have some problem with uploading the video so I upload it on youtube.
https://youtube.com/shorts/1c0ksRJN7...wEIKLV1RJGU-FL