4L60-E Automatic Transmission

Fig.1 Transmission Identification:

Fig.2 Transmission Code Interpretation:

The transmission identification code is located on the rear righthand side
of the transmission above the oil pan, Fig. 1. For code and model interpretation, refer to Fig. 2. The code numbers that indicate the Julian date tell what day of the year the transmission was built. It should be noted that the transmission model year starts in mid year. This means that the first transmission built in any model year will start with a higher Julian date.