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Author Topic: Overdrive Transmission Replacement  (Read 221 times)

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  • Message Board Member not current AMGBA Club Member
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  • Posts: 30
Overdrive Transmission Replacement
« on: February 14, 2021, 01:01:09 PM »
I have a question about a transmission.

Is it possible to take out a 1973 four speed transmission and replace it with a transmission with overdrive? Other than an electrical connections of course.
Tommy K.
Virginia Beach, Virginia.
« Last Edit: February 14, 2021, 01:02:27 PM by JohnTwist »


  • AMGBA Club Tech Staff
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  • Posts: 121
    • University Motors
Re: Overdrive Transmission Replacement
« Reply #1 on: February 14, 2021, 01:03:10 PM »
The simple answer is YES!!

The drive shaft is the same length.  The gearbox mounts are the same. The reverse light wiring (Green and Green/Brown) is the same.  You can move your seat belt warning switch from one remote control housing to the other (if you wanted to – most wouldn’t bother).  The BIGGY here is to test the 3-4 lockout switch TWENTY times to ensure it goes continuous in 3 and 4 (or, if it’s a later gearbox (sidefill) maybe just 4th). 

Change the front and rear seals and ALL the O rings before you install it. 

Hope this helps!
John H Twist
University Motors Online
John H Twist
University Motors Online
100 East Beltline Avenue SE
Grand Rapids, MI  49506


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