|
My experience with 7/9 series window mechanisms points to the pivot point between the two arms (forming an "X").
It does not take much wear to create an uneven up movement. If you find that it is not simply loose or missing screws you may need to replace the mechanism. Because the driver's window usually gets more use they are usually the first to go so finding a good rear window may not be a huge problem.
http://www.brickboard.com/RWD/volvo/1564922/740/760/780/drivers_door_window_failing_seal_top_back_edge.html
That link will lead to my post about replacing the mechanism in a driver's door.
Good luck,
Randy
|