Door Window Vibration Wedge / Thrust Wedge. Porsche 928 1978-95

• Porsche 928 4.5L 1978-82
• Porsche 928S 4.7L 1981-83
• Porsche 928S2 4.7L 1984-86
• Porsche 928S4 5.0L 1987-92
• Porsche 928GT 5.0L 1989-91
• Porsche 928GTS 5.4L 1992-95

The thrust wedge works inside the door window and door shell / door surround area to help ensure the window glass is properly aligned within its track and that the window doesn’t vibrate, rattle, or shift within the door frame.

Symptoms / Signs It Needs Replacing:

• Window rattle or vibration, especially while driving at speed, as the glass isn’t held firmly.
  
• Excessive play in the window — meaning the glass moves or wiggles more than it should.
  
• Misalignment of window, where it doesn’t close flush or track smoothly.
  
• Noise from wind or whistling, particularly around the window/door shell interface.
  
• The wedge is visibly cracked, deformed, or absent when panels are removed.

• Restores precise window alignment and stops unwanted vibration or movement of the glass.
  
• Reduces or eliminates noise, wind whistling or rattles due to a loose or misaligned window.
  
• Protects seals and weatherstrips by keeping glass pressed properly into seals — helps prevent leaks.
• Improves longevity of window channels, glass edges, and seals by maintaining correct tolerances and reducing wear.