1968 Olldsmobile automatic console transmission shifter detents

[bullrun]

Just acquired a 68 Cutlass Supreme with automatic and console shifter. Not a horse shoe /double blade style shifter but a single stalk with knob a 'T' style finger grip. Got it running and noticed right away there are absolutely no detents between any of the positions. Shifted it and tested all aspects and it moves forward and reverse just fine but really  dangerous with no detent/lockouts. It almost rolled of lift. I'm looking into where I can find breakdown/diagram and source for parts to determine what might be missing. I'm new to Oldsmobile and any help/advice would be appreciated. I'd like to repair the stock transmission selector arrangement that is in place.. Thanks in advance

[joe_padavano]

The factory shifter absolutely has a detent feature. It's the curved part to the right of the stick in this photo. You press down on the ball to disengage the lock tab from the detent to allow the stick to move. You will need to remove the console to look at the mechanism and figure out what is wrong. I have two possible causes, both of which are the result of some prior owner incorrectly converting the car to a floor shift. The first is that there are two versions of this shifter, one with a detent for the two speed Jetaway trans (which would be the only AT offered in a 68 Cutlass) and one for a three speed TH400 or TH350 (used in the 442 models and also in the 69 Cutlass line). If this is the wrong shifter for your trans, someone may have disabled the detent feature. The other possible cause is that the conversion was done with the similar but not identical 73-77 shifter. That shifter differs in that instead of pressing on the ball, you pull up on the finger grip to disengage the detent. The detent plate on the later shifter is different and can be unbolted from the shifter mechanism. Finally, it is also possible that the spring that holds the tab in the detent notches is broken, which is another reason why the shifter doesn't engage the detents.

 

This is a correct 1968 shifter. Note the curved detent plate to the right of the stick.

 

 

Here's the 68-style shifter from the other side (note this is actually a 70-72 shifter, which is why it looks a little different from the first photo).

 

 

And just for reference, this is a photo of the 73-77 shifter.

 

Edited November 15, 2020 by joe_padavano (see edit history)