GM TH400 Speedometer Gear 21T

Quality 21-tooth speedo driven gear for the GM TH400 Turbo 400 3L80 automatic transmission. This GM component provides nylon driven gear for correct shift point calibration and speedometer accuracy. The governor system controls shift timing in the TH400, making these parts essential for proper transmission operation in all 1964-1990 applications.

Direct replacement for Chevrolet Corvette, Camaro SS, Chevelle SS, C10/C20 trucks, GMC trucks, Pontiac GTO, Firebird, Buick GSX, and Oldsmobile 442. Precision-manufactured to OEM specifications for guaranteed fitment and reliable long-term performance.