The GM RPO Decoder

Welcome to the GM RPO Decoder!


This is an extension of DataTagDecoder.Com using existing data already present in the database. 


How to use GM RPO Decoder:




Why do I have to enter the Year and GM Division when looking up an RPO code?

  • Most RPO Codes are used and recycled but there are a number of codes that were only used for a couple of years plus the "L-engine codes" are often different between divisions.  We do this in an effort to provide the most accurate data possible.

What is the difference between DataTagDecoder.Com and the GM RPO Decoder?

  • DataTagDecoder provides a complete picture of a cowl tag whereas the RPO Decoder offers a simple quick look when researching one or several RPO codes.

What years does the RPO Decoder cover?

  • The decoder currently translates the same years as DataTagDecoder.Com, 1964-1972.

What do I do if I dont see the RPO Code that I am looking for?

  • There are several things to consider when using the RPO Decoder.  First, make sure the RPO Code was used between the years of 1964-1972.  Second, if there is a missing code, fill out this webform to request addition of the code and include the source where you believe the RPO code comes from.  If you do not include the source, we are unable to add the code to the database.

What is the difference bewteen the Accessory Code and an RPO Code?

  • That is a tricky question.  "Accessory Codes" were only used from 1964 to 1967 on cowl tags, except cars built in Fremont, CA and...  Fremont, ..., used RPO codes in the tag instead of Accessory Codes.  After 1968 "Accessory Codes" were abandoned and replaced wtih RPO Codes.