Is this a new problem? Are we talking about a slant pan or a jetaway? Has the car sat for a extended time? Is it acting as though it is in neutral when it goes into 3rd? Is it skipping 3rd and going on to 4th or only going through to second and stopping there? Have you tried adjusting the throttle / transmission linkage yet? We kinda need more detailed information to give you anything but a wild *** guess . That being said my wild *** guess would be a bad leaky valve body or a stuck clutch piston that is stuck in the release position or incorrect throttle to transmission linkage adjustment . It could be many other things though..... Tedd

 

 

If it's the 88 series, then it's most likely not the Jetaway, but as Tedd said, we need to get much more information from the owner to try to do a diagnosis. And for 1956, whether it's Jetaway or the older Hydramatic, both transmissions had four speeds.

 

Early first generation jetaway's were and are 4 speeds. The confusing part is the same transmission name but completely different transmission.I have no idea why Oldsmobile did that. People have been confused for sixty years and counting..... Tedd

 

Well, on my 56 Jetaway you can't feel first to second or third to fourth. You can feel the fluid coupling from second to third. So if you don't have third, you don't have fourth. The fluid coupling is the problem. Rebuild time.

 

 

If it is the later model Jetaway it is confused with the powerglide. Not so for the first jetaway that came out in 1956.

 

Zach, does the trans have a park position or do you leave it in reverse when parked?