Speedometer Drive Gear
 

Hi Folks-

I need to find out the tooth count on the speedo drive gear in the TH350 trans in my car so that I can get a more appropriate driven gear (rear axle ratio and tire size have changed).

What is the easiest way of finding the tooth count on the drive gear? Is it necessary to drop the driveshaft and the trans tailshaft to get that count?

Thanks

You should be able to count it in the housing. Mark one tooth and spin the shaft, and count.