I have 65 trans in my 63plymouth the trans has a reverse pattern manual valve body . twice when I went from second to drive the rear wheels locked up. is the shifter cable not setup right or the valve . body sticking .it don't do it all the time .thanks
Several things come to my mind, do you know if all the parts on your valve body are for the 1965 or 1963 tranny? If not, or do not know, or if they are part of the 1965 tranny in the 1963 car you will need to have all the correct parts( male end on the shift cable, correct female end on the rooster comb, the correct rooster comb and manual valve for the 1963 tranny in your valve body
I went through this a bunch of years ago at a race back east, one of my customer who had a bunch of early Mopars that he had bought to rebuild and sell swapped the tranny out of a early car an put it in a 1965 Dodge, one of his "mechanics", (parts changers) had swapped a bunch of parts bewteen several trannys and ended up using the 1963 cable shift parts on the 1965 race valve body
We had to find a junk yard and got lucky enough to be able to buy all the parts we needed to fix that job. The female receiver for the 1962/1963 and the 1964 push button trannys are the same, the 1964 and 1965 floor shift tranny use different cables and internal parts and the 1965 column shift trannys use different parts than the other two
The shift cable ends need to match the female ends on the rooster combs, the rooster combs and manual valves to match also
Good luck, let us know what you find and do to resolve this
Fix it right away before you hurt yourself and the car
BTW, you should remove the tranny pan to do the final adjustment on the large shift cable adjuster retainer washer,nut, it will work properly in one hole only
Been there, done that many times when racing those cars years ago
IHTHs