X5 towing experience and fuel economy

[Thecastle]

I don't see a lot of threads on the X5 showing actual towing experiences and I thought I'd start one for people researching the vehicle. I have a 2008 X5 with the 4.8i and I added the BMW hitch. It was a great choice as the hitch system detects when you've installed the hitch shank into the car. It shows when your backing up to a trailer indicators on how to align the car to hitch it up. Awesome feature makes hitching a cinch.

I have a 2017 Flagstaff Micro Lite 21DS which dry weighs 4300lbs and at max weighs 5400lbs well with in the towing capabilities of the car. I use an anti sway weight distribution hitch. The trailer for the most part stable behind the car. The mirrors are perfect and allow a good view around the sides of the trailer. The car was able to keep it going at a steady 65mph-70mph even in very hilly terrain. However I had to keep it in 5th on flat terrain to keep it at 65mph, and manually downshifted to 4th and sometimes 3rd to keep it at speed on hills. Liked that the cruise control didn't kick off when manually shifting the transmission.

I did find that when in drive the car was very aggressive about downshifting on hills and would reluctantly upshift, when it did it would go to 6th and immediately back down to 5th. Found it better to manually shift, to keep the car from hunting and constantly shifting.

Also,now take this with a grain of salt, a lot depends on your trailer, terrain and speed. My micro lite is 8 feet wide and 11 feet tall of brick wall with lots of projections. At 65mph on hilly roads of I averaged 7.5mpg. On flatter ground at 70mph it was about 8mpg. This setup drinks gas.... I'm thinking stops at every 120 miles when I go to glacier next year.... normally I get about 13 around town and about 17-18 on the highway. I'm thinking a tune might help fuel economy if it adds enough low rpm torque to allow me to cruise in a higher gear.

One other bad thing, when backing up the trailer, and only while backing up if you turn the car off. Then back on after backing up, it smokes.... dunno why, I'm going to replace my ccv. It never smokes otherwise. Just when idling and backing up slowly. It's definitely oil you can smell it clearly. Dosent smoke when not towing and when driving forward while towing.

All in all a great but thirsty tow vehicle.