How to Identify the Date on Car Glass?
2 Answers
Glass with numbers and black dots indicates the production year and month. Below is relevant information about car glass: 1. Manufacturing Process: Car glass is manufactured by heating the glass to near softening temperature in a heating furnace, then rapidly transferring it into fans with varying cooling intensities for uneven cooling. This creates different stress levels between the main viewing area and peripheral areas of the glass. Generally, glass produced this way is zone-tempered glass. 2. Classification: Car glass mainly falls into three categories: laminated glass, tempered glass, and zone-tempered glass, all capable of withstanding strong impacts. Based on location, car glass is divided into four types: windshield, side window glass, rear windshield, and sunroof glass.
When I bought a used car last year, I paid special attention to the glass dates, as they are crucial for assessing the vehicle's condition. Typically, you can find markings with numbers and dots in the corners of the windshield. For example, the number 8 with three small dots next to it—dots on the right indicate production in the second half of the year, and three dots represent September. If there are two dots before the number, it means the glass was produced in February of the same year. However, be cautious—the number might represent the last digit of the year. For instance, if the car was manufactured in 2020, seeing a glass marked with '8' could mean it's an older glass from 2018. During my inspection, I once found that the rear window's date was half a year later than the others, and checking the records confirmed it was replaced after an accident. This detail can help you avoid flood-damaged cars. Always cross-check the dates on multiple glass panels to ensure consistency.
