[Tbirdtony]

Hi,
I own a 66 Mustang coupe with the 200 cu. in. 6 cylinder and 3 speed manual transmission. The former owner replaced the 2.77 Falcon/Mustang 3 speed transmission with the 3.03 3 speed transmission which is a more heavy duty transmission and has a synchronized first gear.

I have had a speedometer problem since I bought the car last fall. The speedometer input shaft was gummed up and the speedometer would not move. I had the speedometer repaired, lubricated, & calibrated. The speedometer now won't go above 25 mph and the needle bounces. I replaced the speedometer cable assembly and the gear that attaches to the end of the speedometer cable that goes into the transmission. The speedometer still won't go above 25 mph and the needle still bounces. I even sent the speedometer back to the speedometer shop but the speedometer checks out fine. The only thing left is the speedometer drive gear that is mounted on the tailshaft.

Where can I buy the plastic speedometer drive gear for a 3.03 3 speed transmission? A 4 speed top loader gear will not work. I also want to replace the tailshaft gasket and tailshaft seal. If you know where I can buy these parts please let me know.

Thanks.

 

[Tbirdtony]

tnguy1004 - Mustang parts suppliers do not sell the transmission drive gear. They sell the driven gear only. The drive gear is mounted on the tailshaft inside the transmission. The gears you are talking about are the ones that go on the end of the speedometer cable. I already changed that gear with no change in operation.

 

[Ivy66GT]

You say the toploader part won't work. It won't fit or its the wrong number of teeth?

Here is the part Tony is looking for although this one may not fit a 3-speed.

17285-3

They rarely go bad may be why you can't find any.

 

[Tbirdtony]

Ivy66GT - The 4 speed gear teeth turn in the opposite direction than the 3 speeds. No 4 speed speedometer gear (drive gear or driven gear) will work on a 3 speed. The part you listed only works on a 4 speed.

I am guessing that my drive gear is bad. I have replaced everything else and the speedometer still won't go above 25 mph and the needle bounces. I think the drive gear was damaged when the speedometer input shaft would not turn. The plastic gears kept turning and probably damaged the drive gear.

 

[Ivy66GT]

Call someone like these guys: Rebuilt manual transmissions, transmission parts

When it comes to old transmission parts they almost all now come from a single wholesale shop in Portland, OR. These guys are a retail shop in Spokane who helped me get the parts for my T-10.

If such a gear is available they should know where to get one. It might be only available used? As you can see, most of the sellers don't deal much in 3-speeds.