Do not try and warm it up by idling it. Drive it right away, but moderately

If you have service records showing the transmission fluid has been changed regularly, then go ahead and do it again. If not, changing it now creates a risk of damage

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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
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue