Time for an alignment. If the alignment is correct, tire rotation is not required.

You can rotate, even though it is not recommended, but you will sacrifice ride and handling, as the tires take a set from running a certain way.

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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