The M models (which these aren't) had a recommended first early service, around 2000 km, when they did engine oil and differential oil. The engine oil was due to breaking in of the rings. While it can't likely hurt, I don't see much reason to do a 2000 km oil change in the differential.

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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