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Discussion Starter #1
Hello,

I have a 65 with a 302 & C4 auto tranny. I believe I’ve broken something in the tranny, just looking for advice.

I did a fluid change and dropped the valve body. When I re-assembled everything, I could not physically move the shifter in to drive (I had PRN, however). The tranny manually shifted fine prior to the service.

Ive since checked the linkage, and eventually removed the valve body again to see if I reinstalled it incorrectly (IE did not line up the linkage, etc)

With the valve body removed and the car on jacks, my shifter will still not physically move in to drive. PRN still feel fine when manually moving the shifter. I don’t believe the valve body is the culprit.

Any thoughts? Thanks in advance.
 

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If you drop the pan and disconnect the linkage or remove the valve body, can't remember which, you should be able to manually move the selector through all gears. IIRC there is nothing to get hung up on. I think I put it in Green Dot for mine when I put the valve body back on and before I reconnected the linkage. Also you should be able to remove the pin for the shifter and and manually move the lever through gears.

If you have the valve body out the shift lever on the trans should freely move when disconnected from your shifter. It almost sounds like the actual shifter might be the problem.
 

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Discussion Starter #3
If you drop the pan and disconnect the linkage or remove the valve body, can't remember which, you should be able to manually move the selector through all gears. IIRC there is nothing to get hung up on. I think I put it in Green Dot for mine when I put the valve body back on and before I reconnected the linkage. Also you should be able to remove the pin for the shifter and and manually move the lever through gears.

If you have the valve body out the shift lever on the trans should freely move when disconnected from your shifter. It almost sounds like the actual shifter might be the problem.

Thanks for the response. I just gave that a try, but I still don't believe I'm getting anything other than PRN (with the shifter linkage removed) while moving the selector on the transmission housing. Feels like something may be amiss within the transmission itself.

It didn't dawn on me until now, but I also replaced the selector shaft seal while I was in there. Maybe I incorrectly reinstalled that assembly somehow. I'll verify in the morning.
 

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The shifter linkage lines up with the manual valve on the valve body.
Drop the valve body and make sure the shifter moves freely through all positions.
Then make sure the manual valve moves freely through all positions.
Put the manual valve in the Park position.
Put the shifter in the park position.
Reinstall valve body.
 

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Discussion Starter #6
The shifter linkage lines up with the manual valve on the valve body.
Drop the valve body and make sure the shifter moves freely through all positions.
Then make sure the manual valve moves freely through all positions.
Put the manual valve in the Park position.
Put the shifter in the park position.
Reinstall valve body.
Thanks for the reply. I just posted a video, the shifter is not moving freely. Valve body moves fine by hand out of the tranny. I’m not a transmission guru by any means. Any pointers for what’s next?
 

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I can’t tell from the video but is the linkage connected to the lever you’re moving?
Try moving the shifter handle on the console and/or disconnect the linkage at the trans.
The problem is either the lever on the trans or the linkage from the console.
 

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Discussion Starter #8
I can’t tell from the video but is the linkage connected to the lever you’re moving?
Try moving the shifter handle on the console and/or disconnect the linkage at the trans.
The problem is either the lever on the trans or the linkage from the console.
The entire linkage to the console was removed for the video. The rod that you can see going back and forth in the video won’t move any further forward to the drive gears.

I also removed the selector linkage shown in the video and tried moving the rod by hand, had the same issue. It’s in the tranny, I just don’t know what needs to be replaced.
 

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I believe that internal rod is what engages the parking pawl.
Can you turn the driveshaft when it’s in P?
What about R or N?

Driveshaft should only be locked when in P.
 

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Discussion Starter #10
I believe that internal rod is what engages the parking pawl.
Can you turn the driveshaft when it’s in P?
What about R or N?

Driveshaft should only be locked when in P.
I can turn the driveshaft in R and N only, it’s locks as it’s supposed to in P.
 

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I believe that internal rod is what engages the parking pawl.
Can you turn the driveshaft when it’s in P?
What about R or N?

Driveshaft should only be locked when in P.
This. Something jammed up in the parking pawl would be my guess too. I'll take a peek at my bad shoe video and see if I can find anything.
 

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I can't tell by your video if the cam type part is installed properly. In the video when installing that piece on the shaft it clearly shows more range of motion and it appears to move easily. I would remove the nut on the shaft, pull the shaft and make sure it moves freely. Then push the shaft back in and install the cam-like piece on the shaft and make sure it moves freely. If it helps I could edit a piece of the video showing that.
 

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PM me your email. The video shows the parking pawl shaft connects to the oval lever in front of (or behind) the one on the gear selector shaft, not the one you have it connected to.
 

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After looking at your pics again it appears it is connected to the proper place but something is not right. You can see the bar is interfering with the movement of the cam-like plate. Hopefully the video I sent will help.
 

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Discussion Starter #17
Thanks for that video! I just packed everything up, lost my daylight.

I installed a new seal on the tail housing while I had it off. One more leak solved. Also threw a new vacuum modulator on the tranny since I was there.
For the record, getting the tail housing off while the transmission is still in the car is a PITA. It’s very do-able, but putting it back on will be interesting. The bolts up top are a tight fit.

I’ll get back at it in the morning. Might as well adjust the bands, too. Took a few days off work to get this road worthy before I move in a couple months. This was a surprise problem unfortunately.
 

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Good luck! It looks to me like something is not aligned properly or maybe the bar is bent. When you look at the video the bar is far away from the linkage when you move it but in your pic it appears they are touching and interfering with movement.
 

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Discussion Starter #19
Good luck! It looks to me like something is not aligned properly or maybe the bar is bent. When you look at the video the bar is far away from the linkage when you move it but in your pic it appears they are touching and interfering with movement.
I think you’re on to something, the rod definitely does look bent. I’ll remove it. Good eye!
 

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Discussion Starter #20
Dave,

I feel pretty confident that you found the issue (bent parking pawl rod). I pulled mine, compared it to multiple photographs online and the video you sent me. I straightened it out and now the linkage moves freely. Also loosely connected the floor shifter, and it feels good. Will test again once the valve body is on.

Premature hypothesis- I likely reinstalled the valve body wrong and did not get the linkage lined up in the valve body.

Give me a couple hours to throw everything back together. I ended up doing some maintenance on the driveshaft as well since it was out.

And good lord there was a lot of road grime and gunk on the tail housing. I should have taken a before/after photo. Glad I replaced that seal, too.
 
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