BMW Towing ?
 

I have the 4.4 05 X5 w/the OEM hitch. I have to help a friend by towing their stuff for about 250 miles. He has a Uhaul 6'x12' trailer and we can attach it. Now, with the steptronic, do I have to do anything special, so I don't hurt tranny/engine? Can I drive it in the Sports mode? He has a lot of stuff and will weigh around 4,200 pounds. Also, I have to make another trip towing his trailer (he has another car, so hell drive that back). It is pretty big, around 3 tons. Will I be able to tow this at speeds exceding 80? WIll the back break off or something if I am too fast?

You may think, wtf?, why are you doing this, but he has helped me a lot before when I didn't have much help... So, yea...

Hopefully another board member will be able to answer your questions... but I do know this...

Since you have a refreshed X5, you've got trailer assistance (not sure exactly what it is called). But basically your X5 should be aware of the trailer, and DSC will activate once it detects that the trailer has become unstable...

I have an '05 4.4 as well. I towed a 6'x12' uhaul trailer from Tucson to Chicago with zero problems. I would not use sports mode and there really is no need for it trailering. I would be leary of doing 80 though. Sure you can do it, but might not be as safe. I was doing 80 at times at an elevation of 3200ft, but my mpg was like 2. :)

As for the 3 ton trailer, should be no problem. I towed a 1955 chevy bel air with a uhaul trailer and it was all good. Never even attempted 80 towing it though. The '55 has the aerodynamics of a brick.

Your blinkers will blink faster with the uhaul trailer lights hooked up, that is normal.

I've towed an 8,300 pound GVWR travel trailer for over 28,000 miles without any problem (see my photo & posts on this site) so you shouldn't have any problems. That being said, just remember that if the trailer isn't loaded correctly (about 10% to 15% of trailer weight on the tongue) the tail can wag the dog (sway) and you can rapidly loose control even with the BMW towing functionality interveening.

Regarding the transmission; use MANUAL mode. You want to keep the transmission from "hunting" gears to maintain speed. On my 2001 4.4i 5 speed the torque converter locks-up (direct drive) at about 62 mph. I use cruise control set at an indicated 70 mph in MANUAL mode 5th so the engine can be max throttled (by cruise control) without downshifting or unlocking the torque converter. Your 6 speed transmission should behave the same except the 6th speed torque converter lock-up may be at a different speed than my 5 speed.

I also used a 6x12 Uhaul with my 4.8 and zero problems. Uhaul trailers have surge brakes so you should be fine. The auto dimming rear view mirrors will stop working as the sensor is in the inside rear view mirror which is useless the moment you hook the trailer.

:iagree: To improve your mileage, I'd suggest 60-65 vs 80. At 80 with that much wgt you would be lucky to get 10+ mpg. If it is a windy day, I'd even recommend 50-55 for control. Remember the old Florida license motto, "ARRIVE ALIVE".

You should never trailer at 80 mph... no matter what.

Remember this, if you have a trailer attached to your car and something goes wrong with that cheap-ass rental trailer, its hitch, those cheezy tires, or the way you have loaded it, (tounge weight, wrong balance, incorrect chain up procedures etc)... you are going to be toast.
Having a mishap at 80 is quite different from one at 45.

Trailering a heavy load over a long distance is not a trivial pursuit. Take it easy- read your manual, be cool.

Totaly agree, your X is well equiped for the task but U haul has some of the worst/oldest trailers/trucks on the market. No way would I pull one at 80mph. 60-65 max. IMHO

I think LE in most states would take a DIM view of 80+ mph with a car trailer.

http://www.boatus.com/towing/towlaw.htm

Ok, thank you for the input, I will drive in Manual at 60 mph.

But I was confused, what gear should I leave it in, I have no idea how to do this, this is a first time on any car...