IMO, just as important as not exceeding the rev limits, is to vary the engine speed and load as much as possible. Don't just get on the freeway and sit at one engine speed for a long distance.

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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