Please clarify Towing capacity on 35d

[naka]

Can somebody please clarify the Towing capacity of the X5?

I looked on the US website, have one their catalogues and no information is given.

On this forum, the consensus seems to be 6,000 lb, just like the E53.

But the International BMW website lists 3,500 kg (7,700 lbs) for the 3.5d and 4.8i "in conjunction with optional equipment"; and 2,700 kg (6,000 lb) for the 3.0i.

http://www.bmw.com/com/en/newvehicle...ml?currPage=18

Also, go this link and download the "Models and Technical Data" PDF file.

http://www.bmw.com/com/en/newvehicle...roduction.html

I believe the Europeans use a different hitch compared to the US.

Does anybody know what this "optional equipment" is?