What auto drive mode is recommended for towing?

[js_avery]

I have looked in the manual but towing info for the e70 X5 is hard to come by. I have had the factory hitch and brake controller installed but was curious if there is a recommend drive mode for the transmission. Should I just keep it in drive or put it in d/s or manually shift?

[JCL]

My experience with towing was with an E53, but the principles should be the same. The transmission is a similar design, just with fewer gears.

I started off in the normal automatic mode, never the sport mode, since you don't want higher revs when towing. I wasn't towing over 4500-5000 lbs. When I wanted engine braking down a hill, I used manual mode. At a steady speed, if the transmission had any tendency to hunt between two gears (back and forth, like it can't decide which gear to be in for a given speed) I went to manual mode to prevent excessive shifting.

While it depends to some degree on how much weight you are towing, there are some very good posts by a member named withidl. He towed 8300 lbs of Airstream, over the continental divide, several times. He spent some time monitoring temperatures and transmission functions, and particularly paid attention to whether the torque converter was in lock up mode or not. With it in lockup, you are greatly reducing heat in the transmission, thus extending life. His comments are about the E53, with the five speed, but are still valuable.

Recommend you review these two threads, and particularly the comments by withidl.

http://www.xoutpost.com/bmw-sav-foru...-question.html

http://www.xoutpost.com/bmw-sav-foru...-mountain.html

[js_avery]

Towed my travel trailer this week with the X5 and had no problems. It was a great tow vehicle. Keep in mind I live in Indiana so it's very flat but following the advice in the link helped. Thanks!

[JCL]