Speedometer drive gear question

[craig gaines]

Ok guys, I removed my vss sensor because of a bouncing speedo needle. I changed the cable, still bounces, now I'm looking into the drive gear itself. By all charts I have found, my 2.73-AOD equipped stang should have a tan gear w/ 19 teeth. I pull the one on my car and its grey with 18 teeth. I've counted them several times. Any idea why this is??

 

[dbarr]

Don't know what chart your checking or if you typed your gear ratio right, but both are wrong. 2.73 with AOD is blue 16 tooth. Tan 19 tooth goes with 3.27, which are just your numbers mixed around. Are you sure that's what the ratio is? Gray 18 tooth goes with 3.08, which is what my research shows was the only stock rearend on all mustangs during that time. Anyway, I'm pretty sure that bounce in the speedo is almost always caused by the cable binding. Did the gear look trashed when you took it out? Did you grease the new cable?

 

[FastGT50Stang]

Hey, im just wondering since the thread is already posted, i have installed a 3:90 gear ratio in my '90 fox, which speedometer gear do i need ?

Stan

 

[dbarr]

I'm not sure, 3.90 is not a very popular gear ratio. I would probably go with 4.10 which is white 23 tooth for a T5 and black 23 tooth for AOD

 

[craig gaines]

No, the gear doesnt look chewed up at all. And yes, I greased the new cable. Do I need to like REALLY grease the cable, I just used the little tube that came with the cable. And as far as what chart, I am using the one from 50resto and it says 90-93 AOD 19 tooth w/ 2.73 which according to my door tag, is what I have. The 3.08 is a 20 tooth. What chart did you use. It still doesn't explain why I currently have 18 tooth gear.

 

[dbarr]

oops, your right. I was looking at the earlier model 7 tooth drive gear instead of the eight tooth. So, what you should have had was the gray 18 tooth according to steeda.