Short answer: in your case, no.

It just means that you can't use a weight distribution hitch. Not much of a problem with an auto transporter or similar trailer, as you can usually adjust the carried load front and rear to get a reasonable tongue weight. It matters more with a trailer with more bulk and windage as those trailers will benefit from sway control and weight distributing hitches. If you have 600 lbs of tongue weight (maximum) it means that you are putting over 600 lbs on the rear axle of the X5, and lightening up the front axle (due to the leverage of the location of the hitch ball) A weight distributing hitch puts some of that tongue weight back on the front axle, maintaining steering control. But the linkage involved doesn't work with surge brakes, so it is one or the other.

BMW doesn't acknowledge weight distributing hitches, since they aren't legal in Europe where the design engineers live and work.

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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