This happens in any gear? Video shows going 40 and slipping below 1500 or so.

My xm doesn't grab below 1200 from launch but I've never noticed any issue in other gears.

I can do a test in m/s mode and see if this happens in other gears but you already did what i would suspect should fix it.

Does suggest torque converter to blame which if the case I'm gonna be really upset at myself since i recently replaced my whole motor and had my torque converter in my hands!

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)