Tranny Gear

[GoinBroke]

Does anyone know how many tranny drive teeth on the output shaft for the speedo gear on a C4 in a 69? 6,7,8??

 

[D.Hearne]

I think all C-4's had 7 teeth.

 

[GoinBroke]

Thanks D. Something is sure screwy with mine as it acts like the drive gear is wrong. I have tried the speedgears which should have worked with my combo but it's still off. I guess there is only one way to find out for sure. Can I get to the drive gear by pulling off the tailshaft?

 

[D.Hearne]

Yea, but it's machined into the output shaft. You cannot change it like the manual trans gear. You sure you're using the correct driven gear? The manual and auto gears look similar but they're not.

 

[rbohm]

there are some C4's that have 6 drive teeth.

 

[GoinBroke]

D - I have tried the highest # of teeth of speedo gears possible and still running too high on the speeedo. Do they mahe a calibration box I can install to adjust it down?

 

[D.Hearne]

What rear gear and tire diameter do you have? The highest tooth count driven gear there is , is a 23 tooth. That one's usually correct for 3.70-3.90 rear. 4.11's require a reducer due to the fact that you can't change the tooth count on automatics.

 

[GoinBroke]

3.25 with a 25.1" tire. Any idea what's going on?

 

[D.Hearne]

What gear's on the cable?