Transmission Identification
Transmission ID:
Transmission Identification Label: 3T40 & 4T60
The 3T40 and 4T60 transmission have several variations of electronic control system types. Refer to transmission name plate for specific two letter model and third letter, transmission identification reference. See "Automatic Transmission 3T40 or 4T60 Wiring Diagram" under "Computers and Control Systems"
Automatic Transmissions:
MD9 [1] 3T40 Models
ME9 [1] 4T60 Models
Transmission Control System [2] TCC and computer feedback.
[1] Regular Production Option (RPO) is the Model code stamped on the transmission identification label and the RPO label. (Located on the rear trunk lid.)
[2] Torque Converter Clutch (TCC) is electronic torque converter lockup.
Hydramatic 3T40 models used: BUC, BYC, CHC, KDC, KKC, KNC, LFC, LJC, LLC, AJC, AKC, AZC, LUC, LZC, PDC, PJC, PNC, PRC, PTC, PXC, & TRC.
Hydramatic 4T60 models used: WWH, YAH, YBH, & WFH.