2008 tow hitch picture...
 

Anyone in here installed OEM tow hitch for 2008? Should I installation tow hitch just for bike rack? Thanks

Well, if you want a hitch mounted bike rack, then yes. Other options are roof mounted racks, or the BMW rack that mounts on the rear bumper without a hitch.

Do a search on bike rack, there are lots of posts and pictures, with the pros and cons.

And welcome to the forum!

Here's a pic of my OEM tow hitch with 2" to 1 1/4" adapter/reducer for my bike rack.

If you plan on doing adding an oem hitch, you can do it yourself. You can see a lot of pictures of everything here:

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

I have also attached the installation instructions in case you decide to go for it yourself. Its not very difficult at all and of course much cheaper than having the dealer install it.

If you do it yourself, I think the dealer still has some computer programming to do. At least they told me they did some programming when installing the OEM hitch on my '07.

That is correct. The programming they do is an update for the DSC software that allows it to detect and correct trailer sway. They will charge you for the software update, unless you can get them to update the software under a normal warranty claim (i.e driveability issues etc). Just be sure and tell your SA to ensure the trailer functions are enabled in the update. I used the SIB attached as a reason to get my software updated under warranty (which the vehicle was actually suffering from). :D

I didn't know that. I always assumed it was just to avoid a tail light out warning from the extra lights on the circuit.

I wonder what kind of update reason I'd have for '11 50i....

The module that comes with the OEM hitch integrates without any error lights, because it draws power separately by integrating into the fuse panel. It provides a separate circuit for the trailer lights, in opposed to tapping into the brake and turn signal circuitry. It receives the signals for the brakes and turn signal through a pre-wired connector in the vehicle's wiring harness. Coming up with reason for needing an update with as new are yours is may be an issue. I am sure they will release updates if they haven't already, however the dealers hate performing software updates. If they can't reproduce the issue the update is supposed to correct, you'll be hard pressed to get them to do it.

I don't agree that the software update impacts DSC directly. That is because I have installed two OE hitches (X5 and X3) following BMW instructions, and neither required software updates according to those instructions. Both noted that Trailer Stability Control (TSC) mode would work fine within the DSC programming. TSC is part of the DSC programming, not part of the trailer wiring module.

I think the confusion comes because there are multiple modules within the vehicle, and sometimes the E70 doesn't recognize a new module when it is installed. It simply doesn't know the trailer wiring module is there. The update to vehicle software is required so that the vehicle recognizes the trailer wiring module, nothing more. Once it is recognized, then the existing on-board functions such as TSC, turn signal operation, turning off the rear PDC, all work fine.

This matters because if the turn signals work fine on the trailer, and the rear PDC turns off when a trailer is connected, I don't see a reason to do a software update to obtain TSC functionality.

You are partially correct that the software update is not required, however you are wrong that the instructions don't mention it. I attached the instructions in an earlier post which at the bottom clearly state that programming is necessary. The programming also allows you to use the back-up camera to zoom in to facilitate lining up the hitch ball with the trailer. I would like to see instructions that state the TSC will function without the update. The software update specifically address how the stability control will react to compensate for trailer sway. Will DSC continue to function without the update, of course, it just won't work as optimal as possible. You are correct that TSC is part of the DSC programming, however it is not inherently active. I will have to find the article confirming this and post it so there is no confusion. If you plan on towing a light trailer, or just putting on a bike rack then I wouldn't bother with the update. If you are towing a boat or anything above 5000 lbs. I would strongly recommend it.