Hey new too the forum and I have been hit by the most common failures of the X5-- radiator, expansion tank and yesterday the window regulator. I found it kind of odd that bmw doesnt sale the sliding plastic piece on the regulator. This seems to be the failure point. Any who to make a long story short I paid $100 dollars for a regulator and all is fixed now. I went to ebay and these guys out of Turkey sale the slides and cables for the front and rear regulators for around $20 US anyone tried these? If not it might be a good option for the failing regulator.