Is It Normal for the Manufacturing Date of a New Car to Differ from the Glass Production Date?
3 Answers
It is normal for the manufacturing date of a new car to differ from the glass production date. The reasons are: car glass is produced in assembly lines, and different batches of glass have different production dates. Places to check the manufacturing date of a new car include: 1. Vehicle identification number (VIN); 2. Vehicle nameplate; 3. User manual and related certificates; 4. Trademark on the windshield; 5. Below the B-pillar on the passenger side. Methods to check the glass production date are: 1. Look for the code at the bottom left or right corner of the window glass; 2. The number represents the year, and the dots represent the month. Dots before the number indicate the first half of the year, and the month can be calculated by subtracting the number of dots from 7. Dots after the number indicate the second half of the year, and the month can be calculated by subtracting the number of dots from 13.
When I first got my new car, I was also quite concerned about this issue. After researching, I learned that it's completely normal. Car windows are produced in batches in advance, and it's impossible for the factory to ensure all parts are manufactured on the same day as the vehicle. Typically, the assembly plant keeps a stock of windows and replenishes them with newly produced ones as needed, so a difference of a month or even two to three months in production dates is reasonable. The key is to check if the glass production date is earlier than the vehicle's manufacturing date; if it's later, then there might be something fishy. Each piece of glass has a code in the bottom right corner, where dots next to numbers represent the year. If the small black dots are before the number, subtracting the number of dots from 7 gives you the month. The four windows on my car had a two-month difference in production dates, and after five years of driving, there have been no issues at all. As long as the glass wasn't replaced after a collision, the difference in dates doesn't affect safety in any way.
I actually learned a few tricks from an experienced mechanic during vehicle inspection. The vehicle's manufacturing date refers to when it was fully assembled, while the glass has its own separate date marking. Time differences due to parts inventory turnover are very common. It's like bricks used to build a house might have been fired last year - as long as the glass production date precedes the vehicle's assembly date, it's normal. Key details to check: 1) Verify if all glass date differences are within six months 2) Check if date markings are in consistent locations 3) Look for signs of resealing. On my car, the windshield was made three months earlier than the vehicle assembly date, while other windows were two months earlier - completely reasonable. If all components had to be manufactured on the exact same day, automakers would go bankrupt and parts suppliers couldn't handle such production line demands.
