Greetings. great posts! well, I have the same problem with my sun roof on my 97 E300 d it will tilt and lower ok, but it will not open without force. I tore it apart found the one screw covers and the cables hanging out. Also found the white teflon blocks that slide back and forth in the rails worn out. I am assuming that this is causing the drag on the roof when trying to open itI can't find the parts on the web! The Dealers have a monoply on the parts. you can"t buy the teflon replacement blocks or the yellow bushings you must buy the plastic lifting angle guides 2ea. (2107800133) the actuation roof guide 2ea. (2107820231) and angle 2107800112 (left) and Right (2107800212) Maybe someone out there has a suggestion? Also I am told you are not suppose to lubricate the tracks where to teflon blocks glide, just the cable is that true?