1969 rebuild or replace transmission

Drfn8r
Last seen
Joined
Dec 10, 2022
Thunderbird Year
1969
Hey everyone I’ve about got my 69 running and went to top off the transmission fluid and found it had dumped everywhere I’m trying to find info on the tranny is the ford-o-matic the same thing as the c4 I have a 429 engine and am not sure if it’d be cheaper to replace or rebuild any info is helpful thanks
 

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I would suggest a rebuild. Any compatible replacement is already over 30 years old. And there's a change in the design of torque converters in the early '70s.
So on to your problem. Do you have a cast iron case ( FMX) or one piece aluminum case (C-6)?
Does your transmission work?
It may just need seals, how long had it been sitting?
 
You need to find out where the leak or leaking is coming from? C6 transmission is notorious for leaking IF the Thunderbird sits for more than 2 weeks and no run time. This is normal. Mine 69 Thunderbird leaks from the dipstick tube seal after it sits for two weeks and the fluid drains back in the transmission. If this helps.
 
I would suggest a rebuild. Any compatible replacement is already over 30 years old. And there's a change in the design of torque converters in the early '70s.
So on to your problem. Do you have a cast iron case ( FMX) or one piece aluminum case (C-6)?
Does your transmission work?
It may just need seals, how long had it been sitting?
its been sitting for about two years and it does work the only real problem is you have to hold up the gear selector to make it start I believe its the one piece aluminum (im not home right now to check) ive attached a pic of one spot that definitely looks cracked but i dont believe this is where all the fluid was coming out
 

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its been sitting for about two years and it does work the only real problem is you have to hold up the gear selector to make it start I believe its the one piece aluminum (im not home right now to check) ive attached a pic of one spot that definitely looks cracked but i dont believe this is where all the fluid was coming out
Having to hold the transmission lever in Park is the neutral start switch on the steering column inside the car. Nothing to do with the transmission leak. Typical Ford of the era issue. Consider it a theft deterrent. 😂
It can be fixed with adjustment of the neutral start switch or replacement but they are hard to find with the option of tilt away steering wheel (if you have the option).
Your transmission leak can be possibly be fixed without a rebuild as well (if it operates correctly after warm up (pressure builds).
 
Having to hold the transmission lever in Park is the neutral start switch on the steering column inside the car. Nothing to do with the transmission leak. Typical Ford of the era issue. Consider it a theft deterrent. 😂
It can be fixed with adjustment of the neutral start switch or replacement but they are hard to find with the option of tilt away steering wheel (if you have the option).
Your transmission leak can be possibly be fixed without a rebuild as well (if it operates correctly after warm up (pressure builds).
thanks for the info i was thinking the same thing about the theft deterrant 😂 it has been sitting for about 2 years and i went to drive it around now that the engine is finished but checked fluids first and saw tranny fluid was about empty thats when i filled it up and saw it all over the ground it shifts throught the gears easy enough but scares me i dont wanna toast the transmission do they sell a seal kit and did you happen to look at the other pic i attached im thinking this is one of the places its leaking
 
Not only can you buy a seal kit, all of them except the front seal can be changed without removing the transmission.
 
Not only can you buy a seal kit, all of them except the front seal can be changed without removing the transmission.
huge thanks to everyone who replied ill be getting the seal kit and will give an update did you happen to look at the other picture i sent you where the linkage connects is that a common place to find leaks and do most kits include that seal or is that something different altogether
 
thanks for the info i was thinking the same thing about the theft deterrant 😂 it has been sitting for about 2 years and i went to drive it around now that the engine is finished but checked fluids first and saw tranny fluid was about empty thats when i filled it up and saw it all over the ground it shifts throught the gears easy enough but scares me i dont wanna toast the transmission do they sell a seal kit and did you happen to look at the other pic i attached im thinking this is one of the places its leaking
Could be one of the places that is leaking but was the driveshaft seal. IF you have the transmission rebuilt, replacing all the seals should fix the leaks and C6 transmission is easily rebuilt (should be less than $1k). Not cheap but you will be good for years after that.
 
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