Yep...there is something missing but I could not fine the plastic insulation piece that went above it anywhere to order. So I kept tightening and lossening it before I found the right combination with the parking brake off. According to the W124 manual, you should only have 4 clicks when applying the parking brake (click, click, click, click, tight!). I also adjusted the actual parking brakes on the rear wheels a few turns with a flathead screwdriver (not the easiest thing to do with wheel on) until the rear wheel just dragged a bit and then backed off a little. I did rear wheels once, and parking brake twice and then got it.