How to Read the Date from Car Glass?

[OVanessa]

Method to read the date from car glass: It is represented by numbers and dots. The dots can be either before or after the number. The number indicates the year, while the dots represent the month. If the dots are before the number, it indicates the first half of the year. Subtract the number of dots before the number from 7 to get the month in the first half of the year. If the dots are after the number, it indicates the second half of the year. Subtract the number of dots after the number from 13 to get the month in the second half of the year. Car glass is manufactured by heating the glass in a furnace to near its softening temperature, then quickly transferring it to air grids with different cooling intensities for uneven cooling, creating different stresses between the main viewing area and the peripheral areas. Generally, this process produces zone-tempered glass.

[DeRowan]

That day I accompanied my friend to the used car market and specifically taught him how to check the glass date. First, look for the string of markings in the corner of the windshield—the numbers represent the year, and the position of the small black dots is particularly crucial. Dots on the left side of the number indicate production in the first half of the year. For example, •7 means the first half of 2017, and the exact month is calculated by subtracting the number of dots from 7. That time, we saw the number 3 with two dots on the right side, which meant subtracting 2 from 13 to get November—glass from late 2013. This date should normally be earlier than the vehicle's production date. My friend later used this trick to discover that the previous owner had replaced the windshield.

[BeckettFitz]

Checking the manufacturing year of car glass is quite simple, and here's how I usually do it. First, crouch down and look closely at the four corners of the glass to find a small black dot and number combination code. The number represents the last digit of the year - for example, 6 could mean 2006 or 2016. Dots before the number indicate the first half of the year: three dots to the left of the number means 7 minus 3 equals April. Dots after the number indicate the second half: two black dots on the right means 13 minus 2 equals November. Always compare dates across all vehicle glass - once I noticed the rear window date was three months newer than the windshield, suggesting the rear window had been replaced.

[VonAdriana]

Here's a practical tip: The string of numbers in the corner of the glass hides the production date. The digits represent the abbreviated year, and the small dots determine the month. Dots on the left: Subtract the number of dots from 7 to get the month; dots on the right: Subtract the number of dots from 13. Last week, I checked a colleague's car—the windshield had the number 5 with three dots on the right. 13 minus 3 equals October, meaning it was produced in the fall of 2015. This date should be earlier than the manufacturing date on the nameplate. If it's later than the vehicle's production date, the glass was likely replaced.

[DakotaRose]

Deciphering the glass production date requires some know-how. Last time during a repair, the mechanic taught me to interpret those markings: the number of small black dots next to the digit needs conversion. For example, two dots to the left of the digit '7' means May (7 minus 2); one dot to the right of '9' indicates December (13 minus 1). Note that windshields are typically produced a few months earlier than side windows, but if the date discrepancy across the entire vehicle exceeds half a year, it might indicate prior accident damage. My car's right window glass was dated two years later than others – sure enough, replacement records confirmed this.