Brake controller for E70 experiences

[JCL]

Originally Posted by M3Armand

Bump - any new news on this? Since I am in the market for a trailer to pull my M3 + trailer = 4500 lbs, I need this info as well.

So from what I read, I gather the following:
1) BMW claims our X5 can tow 6000 lbs.
2) We need to have a "brake controller" to legally tow a large amount of weight.
3) The X5 is not "pre-wired" to have a brake controller and we would have to spend extra to have someone install wires to the driver side area in order for an after market brake controller to be installed.
4) BMW's trailer instructions states "Do not use weight distribution equipment" yet doing so is probably MUCH safer. What gives?

No new news, but here is the summary:

1) Yes
2) Not just legally, but safely, which is more important, unless you use surge brakes.
3) Correct, if you use an electric brake controller and not surge brakes.
4) Correct, if you tow heavy weights, ie 6000 lbs plus. Not really necessary for 5000 lbs, but not a bad idea. YMMV. What gives is that BMW is in the SUV business, not the towing business.