Originally Posted by withidl

I'm the guy with the 31 foot 8,300 pound GVWR Airstream which I've towed over 30,000 miles and my 2001 X5 4.4i just turned 90,000 miles.

Your don't have transmission problems, you should just be using MANUAL MODE. I've written about how I use MANUAL MODE which you can look up. In MANUAL MODE the transmission will not "hunt" gears in an effort to maintain speed. In MANUAL MODE you CAN USE THE CRUISE CONTROL (I use it 95% of the time) since MANUAL MODE will allow the engine to be full throttled without shifting (above 60 mph). If you don't use MANUAL MODE when towing you do risk doing damage to your transmission as the constant "hunting" heats/wears the clutches and degrades the transmission fluid.