Ford transmission identification codes include PEA-AG2 for 1973 E100 through E300 vans with 105-inch wheelbases and six-tooth speedo; PEA-AG3 for the 1974 E100 through E300 vans with six-tooth speedo except in California; PEA-AH2 for the 1973 models with eight-tooth speedo; and PEA-AH3 for 1974 models with eight-tooth speedo except California. PEA-AH4 is the code for 1975 through 1976 E100 vans with eight-tooth speedo, drive gear. The vehicles have C4 transmissions and six-cylinder engines. Ford has an extensive list of codes.
Ford assigned dozens of transmission identification codes to its 1973 through 1979 trucks and vans, including F100 through F350 trucks and E100 through E300 vans, and trucks in the M and P series. The automaker also assigned transmission codes to its automatic transmissions in its 1964 through 1972 cars, trucks, and vans and 1973-1979 cars. Lincoln and Mercury cars built with automatic transmissions between 1973 and 1979 have a separate set of transmission codes.
In 1964, Ford debuted its first three-speed light-duty automatic transmission, the C4. It is easy for the automaker to adapt the C4 transmission to many different engine applications because it has a bolt-on bellhousing. Ford, Lincoln and Mercury use the C4 with four-cylinder, six-cylinder and small V8 engines. The 260, 289, 302, and 351W V8 engines all have C4 transmissions as original equipment. Mechanics view the C4 and the C6 transmission, manufactured from 1966 until 1989, as the only two Ford transmissions car enthusiasts should consider.