About DTD

What is DataTagDecoder.Com?
DataTagDecoder.Com is a unique site that provides the ability for the classic car collector and enthusiasts to decode cowl tags on most General Motors vehicles (except trucks) from 1964 to 1972.

Where do we get information from?
We strive to collect the most accurate data from a number of sources including General Motors documents and other collections both online and on paper.

How do I use DataTagDecoder.Com
Select your cowl tag design and using the provided drop down data items, select what you see on your cowl tag and submit for a decoded result.  For detailed instructions click here to select your tag design and click the "How to" link at top of page.

How can I contribute to DataTagDecoder.Com?
You can contribute to DataTagDecoder.Com either financially or by providing accurate data to us via email.

Where can I get a replacement cowl tag?
DataTagDecoder.Com does not provide duplicated or replacement cowl tags.

What is the difference between a Trim Tag, Cowl Tag, Data Plate, Fender Tag, and Body Tag?
All of these terms are interchangeable for the most part.  Fender Tag usually refers to Mopar, and although different, it performs the same function.

What data tags can you decode?
We can decode all General Motors vehicles from 1964 to 1972 (excluding trucks) with more years coming in the future.

What if a code is missing or incorrect?
If there is a code missing or you feel that the data presented to you is missing or incorrect, you can contact us and provide solid documentation for the code you wish to add.  All code change submissions are vetted using the best documentation available.  Your uncle Chuck saying so is not proof, a scanned General Motors document is.

Do you only decode GM trim tags?
At this time we only provide decoding for General Motors products.

Are you planning on expanding the years that can be decoded?
Absolutely!  We are planning on not only expanding our available years back, but also forward depending on demand.

Are you planning on having a decoder for Ford or Mopar?
There are a number of very good Ford decoders on the Internet.  Mopar is one that we have considered and may tackle at some point.

Are you planning on having a decoder for other cars like imports etc.?
Not at this time.

Why aren’t Canadian or European tags included in the decoder?
Those are on the plan.  Canadian tags are relatively easy, European are a little more challenging, but yes we are planning on those.

Why are there so many differences in tag design?
Ask GM!  There were subtle differences between divisions, assembly plants and years, but around 1971-72, GM standardized most of the tags.  Cadillac maintained their own design for some time after.

My tag design does not completely match.  What do I do?
There was a little standardization but a lot of variability in design depending on GM division, year, and assembly plant.  We recommend that you choose the closest design we offer, that should work just fine.  We tried to capture the most common designs, but if there is a design that is more prevalent than we anticipated, we may add the design in the future.

Are all codes shared between GM divisions?
Yes, and no.  Many of the accessory (ACC) codes were shared between divisions, but not all.  When GM decided to use RPO codes in place of ACC codes, data became more standardized.  The most notable difference with the codes are the engine "L-Codes" which was division specific.  You can use the RPO Decoder to get a sense of what that code might be and we are in the process for making those codes division specific.

What if the decoder doesn’t work online?
There are a few possibilities as to why the decoder would not work.  We don’t anticipate any extended outages, but we do have some Internet browser criteria for the best user experience.  At this time we require that you use a computer that is connected to the Internet.  We do not offer an “off-line” or “stand alone” version of DataTagDecoder.Com.

Are you planning on publishing an Andriod or iPhone App?
We are toying with developing a ‘stripped down’ version of the decoder on mobile devices, however getting so much information on such a small screen is difficult.  It can be used on a phone as long as you turn your screen 90*.  It does work but it's not as easy to use, but a tablet works fine.

Can you decode VIN’s?
No, we do not decode VIN’s.  There are many Internet resources out there to accommodate your needs.

How can I tell if my cowl tag is a fake?
DataTagDecoder.Com is not in the business of vehicle authentication.  We can only decode what you present so there is no way for us to tell if your car is a “real” Chevelle SS, or Oldsmobile 442, or Buick GS, etc. Please read our Terms of Use if you need more detail.