Hello all,

I have a 93 z28 that has 3.73 gears in the rear. Currently the speedo is off by about 10 mph. I would like to correct this by replacing the gear in the transmission. Does anyone know what size gear I need to look for?

More info

old rear: 3.23
new rear: 3.73
trans: th700r-4 "auto"

please let me know if there is anything more you need to know

Thanks,

Dennis

 

After doing a little research on [url]www.speeddensity.org[url] I found out the gears that are swapped out in the 93 700R4 trannies are called the drive and driven gears. The part numbers are as follows:

GM p/n 25513052 (44 tooth driven gear) $12.78

GM p/n 8642620 (15 tooth drive gear) $7.56

Can anyone confirm this?

by the way the info was gathered from a post by knightfire on speeddensity.org props to him.