I always found disabling the rear PDC when a trailer is connected to be handy. I also like the fact that with the factory wiring module, when the vehicle senses a trailer is connected it can access a Trailer Stability program in the Dynamic Stability Control if it detects trailer sway.

Towing package is a misnomer. There is no factory towing package in the sense that the vehicles are built any differently. All vehicles are prewired, but only partially.

There is a BMW trailer hitch kit available from dealers that includes not only the physical receiver hitch, but the Siemens module and interconnecting wiring that runs from the factory harness to the plug on the receiver.

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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