There are many more driven gears available than drive gears. In traditional GM transmissions, typically available TH350 (also fits most manual boxes) driven gear selection ranges from 18 to 25 teeth.

Marlan, I am hoping you can help me. I'm running a TH350 tranny in my 1955 Chevy. It has a stock 3.55:1 rear gear, the plastic drive gear has 20 teeth, and I'm running 15-inch tires. The speedo has ...

Speedometer-gear calibration and selection should be an integral part of any changes to your Mustang's chassis or driveline. Changes to wheel and tire size alter the speedometer reading because the ...

Bear with me while I complain like a little girl whose shoes are too tight. I'm sick of answering the same "Why doesn't my speedometer register correctly since I swapped tire sizes?" question over and ...