Decoding VIN Plate on Full Size Chevrolet Impala, Biscayne & Bel Air

Since 1954, all vehicles made in the United States have been assigned a vehicle identification number (VIN). The first few decades of VIN assignment saw no standardized VIN requirements regarding length, character type, etc. The VIN numbers themselves varied depending on the vehicle's manufacturer.

It wasn't until the beginning of production model year 1981 that vehicles were required by (NHTSA) to have the standardized assignment of VINs be a combination of 17 characters (numbers and letters).