missing speedometer drive shaft gear

7173Mustangs.com

Help Support 7173Mustangs.com:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

enginewolf

Member
Joined
Apr 20, 2015
Messages
10
Reaction score
0
Location
United States
My Car
I have a 1973 mustang coupe hardtop that I picked up in March,2015 it has a 351w from a 1994 ford lightning that has been converted to carburetor. Still alot of work to do to it. Looking for help understanding this old ponny
Hey everyone, I have a 1973 coupe that I'm trying to get all the kinks out. What I'm having an issue with now is my speedometer doesn't work. I've checked the cable and it is still working. I can turn one end and guage responds but when I plug it into my tranny and drive the guage reads 0. I looked into the hole when the cable goes in the tranny and I do not see anything but a smooth shaft. I'm under the impression there should be a gear there that turns the speedo cable gear correct?

DSC_0024.JPG

 
The drive gear does appear to be missing. Remove the tail shaft housing to confirm. Chuck

 
There should be a drive gear in there. What type of transmission is it?

 
Sorry. It was stated to me that the tranny was a c4. Since I haven't had the car to long I haven't verified If that's true. But for sake of argument say it's a c4, is the gear supposed to be pressed on? I know some are pressed and some are held on with a type of clips believe.

 
Last edited by a moderator:
The gear is held on by a snap ring. There is also a small ball bearing that holds the gear in place which keeps it from spinning on the shaft. It is real easy to replace once you have the tailshaft removed. Since your gear is missing completely, I'm guessing the snap ring and bearing are missing as well.

 
10-4 thanks alot. I'll start to tackle that job today

 
So Ive started on the job and I have found out I have a 1977 C6 transmission and not a c4 transmission like originally state. and the drive shaft is bare no drive gear anywhere to be found.

DSC_0028.JPG

 
Last edited by a moderator:
Kudos for tackling it yourself so quickly. If it weer me I'd stop by a transmission shop. They are likely to have some core transmissions or parts in their bins to get you what you need. Or they can refer you to the correct part source with a part number to order.

 
Thanks for the website but I don't have a 4 speed, it's a 3 speed automatic

 
Has 2.8 rear end and 265 r15s I didn't think that stuff mattered for the drive gear that goes onto the output shaft. I thought that info was needed for the correct speedo driven gear.


I'm starting to believe it was supposed to have a metal drive gear cut into the shaft itself honestly. Just not sure why it wouldn't have it then.

 
Last edited by a moderator:
Thanks for the website but I don't have a 4 speed, it's a 3 speed automatic
Sorry about the brain fart. I guess I'm four speed obsessed this week, putting a clutch in my other car. Chuck

 
Back
Top