On Camaros.org there is a section about understanding the date codes of LOF glass...does anyone know if this applies to PPG glass as well? I have the following markings I can't figure out...(on my Impala 4-door)

Windshield: PPG AS-1 1-29 M25 DOT 18
Rear Window: PPG AS-2 27-29 M20.8 DOT 18
Driver’s Front: PPG AS-2 27-49 M27.8 DOT 18
Driver’s Rear: PPG AS-2 26-29 Unreadable
Passenger Front: PPG AS-2 27-29 M20.8 DOT 18
Passenger Rear: PPG AS-2 26-29 M20.8 DOT 18

I know AS-1 is for windsheild and AS-2 is for the rest of the windows, and Camaros.org explains the DOT 18...what I need to know is the M20.8 - and I think the 27-29 is a model number and tint...since they are all "29" except 1 which I know is not original as it has the soft ray tint "49"

Interested to see if anyone knows...

Yeah, I found some stuff, but it doesn't fit exactly to the older templates. I can tell you that the first digit in the code (e.g. - 26 -27) stands for the manufacturing plant.

I believe they are:
1 - Creighton, PA works
25 - Greensburgh, PA works
26 - Crestline, OH works
27 - Tipton, PA works
28 - Evansville, IN works
41 - Berea, KY Works
81 - Oshawa, Ontario works

The second digit appears to be a date code with the last digit being the year of manufacture. I am still checking into this...

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Steve


From way back in 03... had to do some searching to find it.....

I never did finish the PPG part of the glass article, but I probably have enough info now to add a brief appendix.

M20 is a PPG internal code for a particular type of glass, and the .8 indicates the thickness of that type in 1/32s of an inch. So in this case, M20.8 indicates 1/4-in thick glass of type M20.

M27 happens to be tinted glass of the otherwise same type as M20.
M25 is laminate windshield glass

It is correct that the digits to the left of the hyphen are the manufacturing plant code. PPG told me that only Plants 1 and 26/27 would apply to Camaro. Plant 1 being for laminated windshield glass only. 26/27 for side/rear.

I can confirm that

25 is Greensburg, PA (non F-body)
26 is Crestline, OH
27 is Tipton, PA

The other codes you list are additional info that I didn't have, so appreciated. If you have the source I'd like to quote it.

The digits to the right of the hyphen are the month/year, such that 29 is Feb 1969, 49 is April 1969, etc.

Rich

The other codes you list are additional info that I didn't have, so appreciated. If you have the source I'd like to quote it.


Me. I work for PPG! ;)

My boss and I dug through some old information and called some old glass guys at Creighton and Evansville and found those plant codes.
It is all from memory... but I am 95% sure that they are correct....