Author Topic: Speedometer gear  (Read 1042 times)

Offline A110235

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Speedometer gear
« on: March 12, 2014 - 10:42:45 PM »
I went for a drive this weekend and my new speedometer didn't work.  I disconnected the cable from the 4-speed and I can spin it with a drill and it reads right at the gauge.  What would be the problem in the transmission?  I took the retainer off and started to pull the housing where the cable connects at the trans when I discovered it was a really fast way to empty the all the fluid.  :banghead:  What will be the fix for this?

Kyle



Nashville, TN         Member since October 09, 2004




Offline 67vertman

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Re: Speedometer gear
« Reply #1 on: March 12, 2014 - 10:48:47 PM »
It is just a plastic gear inside, it could have broken or is stripped, and yes removing the speedo gear will drain most the fluid from the trans, I found out the same way you did.  :bricks1:

Put a drain pan under it to catch the fluid, if you want to reuse it.



Ron - Born and raised in Southern California

I got the 1970 Cuda, but still need the hot blonde to ride shotgun!

First car -1969 Road Runner 383 4sp

Current ride - 1970 Barracuda 440-6 4 sp Dana 60  (4:10)

Offline A110235

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Re: Speedometer gear
« Reply #2 on: March 13, 2014 - 12:03:56 AM »
Ok, thanks for the info.  I assume they are still available, where can I get the gears from?  And how do I know which one I need?  Isn't there some formula for which one I would need based on tire height and rear gear ratio?  I'd say it is a pretty slim chance that I have the correct one where my speedometer would read right.

Kyle



Nashville, TN         Member since October 09, 2004

Offline Chryco Psycho

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Re: Speedometer gear
« Reply #3 on: March 13, 2014 - 12:48:44 AM »
The speedo drive has to be clocked so the gear will mesh properly with the output shaft .

Challenger - You`ll wish You Hadn`t

Offline A110235

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Re: Speedometer gear
« Reply #4 on: March 13, 2014 - 09:54:27 AM »
I'm not looking at it now, but I remember the two prongs of the retainer seated in two little notches in the body of the housing.  Maybe it is 180* out?  Is there anything that helps to show what the proper alignment is? 

Kyle



Nashville, TN         Member since October 09, 2004

Offline Chryco Psycho

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Re: Speedometer gear
« Reply #5 on: March 13, 2014 - 07:18:09 PM »
Yes , the housing has 3 group markings for different tooth counts so it has to be clocked according to the tooth count

Challenger - You`ll wish You Hadn`t

Offline 67vertman

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Re: Speedometer gear
« Reply #6 on: March 13, 2014 - 10:53:09 PM »
This helps a lot in slecting the right gear to pinion ratio

http://www.moparts.org/Tech/tech/pages/speedo.html



Ron - Born and raised in Southern California

I got the 1970 Cuda, but still need the hot blonde to ride shotgun!

First car -1969 Road Runner 383 4sp

Current ride - 1970 Barracuda 440-6 4 sp Dana 60  (4:10)

Offline A110235

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Re: Speedometer gear
« Reply #7 on: March 13, 2014 - 11:10:17 PM »
Sweet!  Thanks for the info guys.

Kyle



Nashville, TN         Member since October 09, 2004