How do I determine which transmission is in my 350 4bbl cutlass s?

 

Assuming its an automatic, this may help. A chart to identify and confirm oil pan shape.



From post #6 of the following thread. https://classicoldsmobile.com/forums...n-swap-127939/

 

I thought the automatic Cutlii had a TH350?

 

Jetaway in 1968. TH350 didn't exist yet. Unless someone swapped it into Beehalls car.

 

^^^THIS! The standard and ONLY automatic trans that was available in the 1968 Cutlass was the ST300 (Jetaway) two speed. This is not a Powerglide.

 

So, for starters, drive it and see if it shifts once or twice.

 

Look at the shift indicator on either the speedo or console. It will indicate two forward positions, drive and low. As stated it should be a jetaway if original to the car.
If it blows up replace it with a BOP TH350.
Service it and change the fluid at least two to three times in a short period to get fresh fluid throughout.

 

In most of the Jetaway to TH350 swaps I've seen (including the two I did), nobody bothered to change the shifter quadrant.