Transmission Problems. Please help

[billysdad]

I recently purchased a 1968 Plymouth GTX and I am having trans problems. It wont shift into 3rd gear. I am new to Mopar and not sure what triggers the trans to shift. Is there a vacuum line that goes to the trans? I did notice that the linkage from the carb to the trans is missing. Is this linkage only for the passing gear or does it have something to do with my problem? Any help would be greatly appreciated

 

[monaco66coupe]

You apparently have no throttle kickdown linkage . There is no No Vacuum on setup, like ford and GM on your Mopar. The carb throttle has linkage to adjust the pressure needed to tell the transmission what to do. You need it to shift properly through all the gears.

 

[dvw]

I'm assuming 3rd gear isn't slipping, just that it never shifts into 3rd. Look above the shift linkage attachment on the trans. There should be another lever on the same shaft that normally connects to the throttle pressure linkage (kick down linkage). Is it there? Is it pulled rearward and wired back or tie strapped back? If so the trans thinks it's at wide open throttle. It may shift into 3rd at high rpm. A stock Torque-Flite will not operate properly with out throttle pressure linkage. The line pressure will be low causing clutch and band damage. If the linkage is missing some people wire back the throttle lever to increase the line pressure as a band aid for missing linkage.
Doug

 

[mopar 3 B]

Did the PO say anything about possibly a manual valve body? If it has a manual valve body there will be no kick down linkage and you have internal trans problems.