The parts need extra adhesive to be more secure.
A manufacturing issue may let the glass separate from the frame because of a problem with the adhesive's application. If the piece detaches, it could distract the driver and create a road hazard. Plus, there would be a gaping hole in the sedan's roof.
Audi first learned of this problem in winter 2015 when it received complaints about the issue. It began investigating and eventually discovered the cause. The company will notify the affected owners by mail in July. Dealers will add extra adhesive between the glass and sunroof frame for extra security.
These models were Audi's flagship luxury sedans at the time. They came with cutting edge technology for that period, including the premiere of the MMI infotainment system. The S8 used a 5.2-liter V10 and six-speed automatic. They could get to 62 miles per hour (100 kilometers per hour) in a claimed 5.1 seconds and had a limited top speed of 155 mph (250 km/h). Audi replaced this generation of A8 with the current one for the 2010 model year.