New Obsolete Stock is a term commonly heard when dealing Ford parts but rarely GM. I have askied this question many times to a few GM parts managers and most seem to fall into the catagory of Nos meaning new old stock
New- never installed or used
Old- manufatured years ago
Stock- original GM inventory stock of an original design
One individual used the obsolete version at a certain stage which his justification being.
The item is classed as old as long as it is still available in either the GM parts book or the slow mover list, once it is removed from both locations it is now New obsolete stock.
I liked his take on it
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