Well, I'm currently typing this as I await a tow truck on the side of the highway so please forgive the grammatical errors.

72 4 cyl with a factory tail shifter.

I was driving down the highway and had shifted into fifth and was continuing to accelerate to a cruising speed when the car held for about 3-5 seconds then popped out of fifth. I tried to put it back into fifth and it would not go in, it wasn't there. I could place the shifter, release the clutch, and the car would just rev. I dropped down to fourth and it was there and held in place. I continued along and then tried for fifth again, nothing. Went back to fourth and it was gone along with everything else. Coasted to the side of the highway and shutdown.

On the side of the road the clutch appears to be engaging and disengaging as it should. When I move the gear shift there is an noticeable difference in feel, therefore no resistance to movement and no noticeable notch into the gears.

Under the shifter looks good, the bolt before the firewall is still tight connecting the two front and rear sections of the rods.

From looking under the car (I have not gotten it jacked up yet) the firewall bushing appears to be intact and in place. The rods are connected immediately aft of the firewall. At the tail I can move the lever in, out, and fore and aft, but there does not feel like it's connecting and going into any gears.

I've searched a bit and read something about an internal roll pin in the tail of the transmission. Not sure if that's my problem. Need more research.

I'm now sitting in the tow truck headed home. Opinions and thoughts welcome and appreciated.

Thanks

Definitely. Check the roll pins at the rear firewall (pull the boot back). And under the plastic cover at the rear of the trans. Sounds like one is loose or gone.

Will do. Thanks

Just got home. Lunch, then get it up on jack stands.

Edit: not sure this stuff applied to my tail shift transmission. I'm thinking this is for a side shifter.

I don't know how to fix your car but I know about being towed!
Click to view attachment
Paul

Now your a member of the flat-bed thread!

Sorry to hear this! Don't have an answer for you but would love to know the solution for future reference! Just in case!

Pretty sure I found the problem. Video below...

http://i33.photobucket.com/albums/d66/lami...zps2mpzqafr.mp4

Pretty sure that's not supposed to do that.




So I'm guessing the pin (#11) inside has sheared off of part #14. Anyone agree or disagree?


Now that I'm possibility on the right track I need to order some parts and confirm I'm doing this correctly.

If I pull that rear cover plate (#9), I'm going to dump most, if not all of transmission fluid correct? So I might as well just be prepared to drain the fluid?

And then I'll need to punch out the old pin, press in a new one, and refill the tranny. Am I missing anything here? Does anyone have a part number for #11? Or a link?

Since I've got the rear rod disconnected from the transmission I'm considering doing the remaining bushings. I'll have to wait a few days for the pin to arrive anyhow.


Thoughts???

Already been there!! Hahaha

I replaced the shift seal in my tail shift transmission recently, so I got to know the suspect pin very well. It is a steel roll pin and very strong. I had a hard time getting it out! Doesn't seem to be a common failure point, but possible. When you operate the shift lever, does it move in the cage at the transmission end? You mentioned that the feel of the shifter at the lever was different, so maybe there is a problem with the pinch bolt at the adjustment point for the linkage, #29 below, or with the several plastic bushings in the shifter system, which need to be replaced every 20 years or so....Let us know what you find
Click to view attachment

Thanks for the input

The pinch bolt you mention is tight and the two rods are securely attached.

When I shift with the lever, the rod moves the cage as it should

I'm leaning towards the pin because the rod that the cage attaches to and goes into the transmission (#12 in my pic above) is able to spin a full 360 degrees. If the pin were in place as it should be I don't believe that would be possible. Am I correct?

I'll likely be draining the transmission tomorrow.

You are most likely right.
Either that pin fell out, sheared off, or the lever part itself (part #14) broke.
I am fairly certain I replaced that pin once before to install new seals.
A small drift pin & tiny c-clamp rings a bell...

Yep. I'd put $ on the roll-pin too.

T H O M A S fab'd a cool little press tool to remove the roll-pin when we were rebuilding the tail-shifter from my '71 - as we needed to replace the selector shaft seal.

Removing the bottom cover plate (#9) will allow you to look inside and determine if it's indeed a roll-pin failure or not. The pin might even fall out when you pull the cover off, so keep an eye out for it.

Thanks for the info. Interested to see this tool. I was just planning to try a punch.

Thanks for the info. I'll let you guys know what I find.

Drain the gear lube BEFORE you remove the access plate (#9)! Have the catch basin ready as some of the lube will still be on top of the plate. You will need a new gasket for the plate. Now might be the time to go thu all of the linkage bushings.

Thanks for the tips. Need to order the gasket and pin.

Well, just got back from the garage. It's confirmed, the roll pin gave out. For reference in this discussion the pin is #11, the cover plate is # 9, and the pin attaches #14 to #12





You can see the pin sticking out from both sides from the selector in the pic above. Now watch the pin fall out in the video below...

http://s33.photobucket.com/user/laminar/me...gboq6m.mp4.html

So that's not right. Here's some more pics of the pin and it's home.






Good news is I know what the failure was and it's relatively cheap. Not necessarily bad news, but more I need input on is...

1. I'm not an expert, I'm new to this so expert opinions needed. When I pulled the magnetic drain plug there seems to be a significant amount of metal on it. There was also a good amount of flakes in the pan. Is this excessive and cause for concern?





2. The plate was sealed with the gasket, and silicone. I remember Dr. Evil saying that silicone should almost never be anywhere on these transmissions. Is that correct? Could the silicone cause havoc internally? Is it possible that the gasket was not sealing the cover plate in the past and the silicone was added to help? Pics below...




I've cleaned the silicone off and am now needing to make some decisions.

Option 1. Order the pin and a gasket. Easily the cheapest and easiest to get the car back on the road. This of course assumes that the metal on the plug and the use of silicone is not a major concern. I will also be replacing all the bushings.

Option 2. I've found a side shift setup for a very good deal. The condition of the trans is unknown, but a trans is included. All other items for the swap are included, EXCEPT one of the shift rods was cut to ease removal from the previous car. I may need to source another bar, or hypothetically I assume a skilled welder could splice the bar back together. I could perform the swap or may take it to the shop.

Option 3. Buy the above mentioned side shift setup and convert my current tail transmission to a side setup. Definitely the most work and would require the help of a professional.


If you're reading this years from now, these part number may help you get what you need to fix this. I researched in PET and these are the part numbers I found, I have not confirmed they are 100% correct yet. Location in PET pages. 113-114, illustration # 302-05

Roll pin #18 = 900-303-013-00 (specified as 5x24)
Plate Gasket #20 = 914-301-391-00
Gearshift lever #17 = 914-303-013-01 (not needed for replacement here, but included for reference)
Bellcrank #16 = 914-303-301-01 (also not needed for replacement now)




Alright people, I need your input!!!

Convert it to a side shift. You can do it yourself, it's not that hard!

I have those tail shift pieces for free, if ya want. I usually toss them. Seal, too. Technically, sealant is not recommended, but at that location you wont goof up anything unless you get crazy with the application. I have side shift convert pieces for internals and box. If you have all externals and box is included, that's a great start. Conversion is not too bad, you will need the alignment jig for the forks, tho.

Thanks for the offer. I'm going to follow up on the side shift setup tomorrow and see if I can scoop it up. If not, then yes I'd appreciate whatever you can offer to get me up and running. The pin and gasket etc.

Any thoughts on the amount of metal on the drain plug? Should I be worried about the internals at all?

I've read a bit on the tail housing to side conversion. I'll have to read it all again. I've never opened a transmission before.

Double post