Why are the dates on the rear glass of a new car different?
2 Answers
It is normal for the dates on the rear glass of a new car to be different, as long as the production date of the glass is earlier than the manufacturing date of the entire vehicle. This is because car glass is installed after the vehicle is produced. The glass is uniformly procured by the manufacturer in advance, and due to different procurement batches, the dates may vary. Car glass is produced by heating the glass in a furnace to near its softening temperature, then quickly transferring it to cooling zones with varying intensities to create uneven cooling. This process results in different stress levels between the main viewing area and the peripheral areas of the glass, typically producing what is known as zone-tempered glass.
It's quite normal to find different dates on the rear glass of a new car. The date codes on automotive glass, such as numbers with dots like '3·15', indicate the production year and month. Sometimes, glass from different batches may have varying production dates. When manufacturers assemble vehicles, the windshield and rear glass may come from different suppliers, or inventory management may result in some glass being produced earlier as spare parts. Workers on the assembly line then install them according to batches. New cars undergo strict quality inspections before leaving the factory, and as long as the glass is intact without cracks, it won’t affect performance or safety. If you’re really concerned about a significant date difference, you can check the vehicle records with the dealership to confirm it’s a factory-new car. By the way, other parts of the car, like door trims, may also have different dates—this is standard practice in manufacturing, so there’s no need to worry too much about it.
