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57-82 Speedometer Driven Gear - 21 Tooth - Red

Item #:
TM-155
New reproduction 1957-1982 Corvette 21 tooth speedometer driven red gear. Speedometer driven gears mount inside manual or automatic transmission where the speedometer cable attaches. Gears vary upon transmission, differential ratio and tire size. Correct usage can be identified by # of teeth and color of gear. Gears are often found broken and unable to properly drive the speedometer cable OR need to be replaced to provide more accurate speedometer readings due to changes in tire size or differential ratio.

Note: Changes in gear can affect how the speedometer reads. If you speedometer is reading fast, install a gear with more teeth to reduce speed. If your speedometer is reading slow, install a gear with less teeth to correct speedometer. One (1) tooth = approximately 1.5 mph. Gear sleeve may need to be changed when changing the gear usage.

(GM Part 3987921)

More Information
Model Year 1961, 1962, 1963, 1964, 1965, 1966, 1967, 1968, 1969, 1970, 1971, 1972, 1973, 1974, 1975, 1976, 1977, 1978, 1979, 1980, 1981
Base Unit of Measure EA
Search Description C1 C2 C3 C4 TRANSMISSION GEARS TEETH TOOTH
Net Weight 0.001000
GM Item No. 3987921 3860344
Additional Item Information
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