I have a 89 Firebird that i recently bought and the owners before had to replace the automatic transmission because they said it broke. when i bought the car i grabbed the old trans cause it thought they had no clue what they were talking about. when i bout the car the speedometer did not work and i thought it was just the cable or something. when i climbed under the car i saw the transmission they put on had a port for a cable speedometer cable but my car had a electric speedometer. so i went and looked at the old trans and pulled out that and compared it to the current trans speedsensor. the old speed sensor has 37 teeth and the new sensor has 32 teeth. i will attatch a picture to give a visual to the problem, but will the diffrent number of teeth affect the speedometer greatly??

the speed sensors
http://s977.photobucket.com/albums/a...peedsensor.jpg

the gears
http://s977.photobucket.com/albums/a...0515101835.jpg

 

Check out these Sticky thread (at the top of the Transmission and Driveline page), and get back to us if you still dont understand.

https://www.thirdgen.org/forums/tran...eedometer.html

https://www.thirdgen.org/forums/tran...eedometer.html

 

thanks so much i was looking in the wrong section and under the wrong posts those other posts are so helpful, thanks again