PDA

View Full Version : 89sc speedometer error



Tom Mack
06-11-2005, 01:50 AM
My speedometer reads fast. 3MPH at25 & progressively higher to about 8MPH faster at 80. The tires are new & are the correct size(225x60-16). Has anyone had this problem, & what is the cure for it if you have found one? It's an AOD trans.

blksn8k
06-29-2005, 08:58 PM
My speedometer reads fast. 3MPH at25 & progressively higher to about 8MPH faster at 80. The tires are new & are the correct size(225x60-16). Has anyone had this problem, & what is the cure for it if you have found one? It's an AOD trans.

I ran into the same problem when I replaced the original Gatorbacks with Dunlop SP Sport 5000's in the same size. I haven't corrected mine yet but here is a link to a calculator. The only problem with using this is that you need to know how many teeth are on the drive gear. That is the worm gear on the transmission output shaft that drives the plastic gear on the end of the speedo cable. This calculator will determine what tooth count is required for the plastic driven gear. You also need to input the rear axle ratio and tire diameter. Anyone know the tooth count on the drive gear? I'm guessing it is either 7 or 8. :confused:

http://home.att.net/~jroal/drive.htm

blksn8k
07-07-2005, 07:33 PM
ttt ttt ttt ttt