1980 CHEVROLET TRANSMISSION IDENTIFICATION C21 NOTE Transmission Iiientilieetion can be Located in One of Three Positions oh the Transmission A Identification Plete on Side of C se B Stampfng Number on Governor Cover C Ink Stamped on Bell Housing A SERIES ASSEMBLY CODES MI5 3 SED MAN M20 4 SPD MAN MVS 3 SPD A T ZG Z8 7CC 7CA 7Cl M33 3 SPD A T M38 3 SPD MV4 SPD A T 7KC 7KJ 7JK 7JJ 7WD KT 7JE 7XN M31 3 SPD A T 7WL 7XL B SERIES ASSEMBLY CODES MV9 3 SFD A T M31 3 SPD A T M33 3 SPD AT 7CC 7Cl 7WL 7WH 7JE 7KD 7CE 7XL 7XK M3B 3 SPD A T MV4 3 SPD A T 7JA 7KH 712 7VVC 7JS 7WD 7XV F SERIES ASSEMBLY CODES M15 3 SPD MAN M204 4 SPD MAN M21 4 SPD MAN SF SR FN M33 3 SPD A T MV9 3 SPD A T M38 3 SPD A T 7MT 7JL 7CK 7KF 7JD 7JJ 7JK 7JL H SERIES ASSEMBLY CODES M20 4 SPD M T M29 3 SPD A T M38 3 SPD A T SH 7PA 7PB 7KA 7PY 7PC T SERIES ASSEMBLY CODES MY1 4 SPD MAN MD3 3 SPD A T M29 3 SPD A T UH UK JC TW 7CN SM SN WK VN ssmss ASSEMBLY cones M20 4 SPD MAN M34 3 SPD A T AT 7CV 7PZ AU GM PARTS DIVISION GENERAL MOTORS CORPOHATIQN CHEVROLET 10 S6