Why It Matters
A wide-ratio four-speed was standard; M21, M22, and M40 Turbo Hydra-Matic were alternatives. Case, stamp, date, ratio, shifter, linkage, drivetrain compatibility, and paperwork must agree.
Also Known As
1971 Corvette four-speed1971 Corvette M211971 Corvette M221971 Corvette Turbo Hydra-Matic