Towing with a 2007 X3
 

We bought a 2007 X3 3.0si (260 hp) a few years back, but never got around to installing a hitch. I put an OEM hitch and wiring harness on in January this year, thanks to the very good instructions posted by X3eme, and the BMW factory service instructions that my dealer printed out for me. It is a lot easier than the X5 hitch that I did in 2003, and took about 2 hours with two of us not rushing at all. We did have a hoist, so we had the bumper at a convenient working height. A couple of comments on the install:

• We didn't need to take the bucket out of the right rear of the luggage compartment. Instead, we removed the air filter from the outside (under the bumper cover on the right side) and that gave clear access to connect the wiring.
• The instructions suggest leaving out the clip-in trim piece on the 2007 and newer models (it is black, and rectangular). If you leave it out you need to use a black spray bomb to cover various exposed bits. We did it more neatly by trimming the cover to the 2" square receiver, about 1/4" space on three sides. We also had to trim underneath on the left of this trim piece for the electrical connection. With that done, the hitch is beautifully finished, and the cover is easily removable if you need more access to a locking pin.
• There is no vehicle recoding required according to the factory instructions. They are explicit on this point. All lights and PDC cancel worked perfectly. No fast blinking.

We towed a U-Haul from Vancouver to Calgary last week, about 1500 lbs trailer weight (estimated, not scaled). This was through several mountain passes, in winter conditions. I wasn't worried about the vehicle brakes at that weight, but I did use the manual transmission on long downhills in the Rockies to avoid heating them up too much. We had a full load in the vehicle as well, and we were able to pull 6th gear fine on most grades, 5th sometimes, and only required 4th on two of the steepest grades through the Coquihalla (10%). That let us cruise at 110 km/hr with the speed control.

The X3 towed beautifully. It isn't as heavy as the X5, but it had more power than my 3.0 X5, and the manual transmission is nicer for towing.

By measuring fill ups, we calculated 11 litres/100 km on the trip out fully loaded and towing at 110 km/hr (equals 26 mpg Imperial, 21.5 mpg US), and 9.5 litres/100 km coming home at 120 km/hr cruise, fully loaded but with no trailer (equals 30 mpg Imperial, 25 mpg US)

A good 2500 km road trip. Two photos attached. We did specifically find a U-Haul trailer that was the same height as the X3, to reduce windage.

Jeff