The Hydra-Matic 4L30E automatic overdrive transmission identification plate for the production unit is located on the driver's side of the transmission near the selector switch. The transmission code (1), the production serial number (2), the part number (3), the calibration code (4, 5) and the application and torque rating (6) are shown.

The transmission identification plate for the rebuild unit is located in the same location as the production unit with variances in the breakdown, the transmission code (1), the production serial number (2), the part number (3), the remanufacturing build week (4), the remanufacturing build year (5), and the R designation.