It seems to me that with an automatic transmission, there are only two options for the transmission while you are revving it up. It can be working against the torque converter (producing a lot of heat) or it can be in neutral, in which case releasing the brake would then slam it into gear at high revs. That would be brutal as well. I think it is far more likely that it is in fact working against the torque converter.

At the end of the day, it is an automatic transmission.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
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