| Subject: | Rear and Side Tempered Glass Spots (Quench Marks) | |
| Models: | 2021 and Prior GM Passenger Cars and Trucks | |
| Attention: | This PI also applies to any of the above models that may be Export from North America vehicles. |
This PI has been revised to add the 2020-2021 Model Years. Please discard PI0754C.
Some customers may comment on spots showing on the rear and side windows when the vehicle is in the sunlight. When wearing polarized glasses/sunglasses, these spots may be more magnified.
The spots are due to the manufacturing process and are “quench marks” in the glass. Quench marks are an unintentional side effect of the tempering process.
Technicians should explain to the customer that this is a normal condition and part of the manufacturing process for tempered glass. Do not replace the window(s) for this condition.
Note: This will not be seen on front windshields or laminated side glass.
Article ID: 1470
Created: November 11, 2020
Last Updated: November 11, 2020
Online URL: https://www.corvetteactioncenter.com/tech/knowledgebase/article/1984-2021-corvette-service-bulletin-pi0754d-rear-and-side-tempered-glass-spots-quench-marks-nov-6-2020-1470.html