All automatic transmissions have a metal identification (ID) nameplate (1) attached to the case exterior.
The Hydra-Matic® 4T40-E transmission has a metal identification nameplate (1) attached to the case exterior.
The information on the nameplate assists the technician in servicing the transmission and ordering replacement parts from a GM Parts Catalog.
Additional transmission identification information is provided on the Service Parts Identification label. This label shows the regular production options (RPO) as well as the standard and mandatory options. This label is affixed to the inside of each vehicle at the assembly plant.