Sarum

I have read (Wiki maybe) that the above car came out with a 2 stage auto and also that it had a 3 stage. Mine has a 3 stage and I am trying to find out if it should be a TH350 or what?
Thanks in advance

nsnarsk65cutlass

ST 300 two speed with variable pitch stator torque convertor.No TH 350 in 1965.

jaunty75

The two-speed automatic is called the "Jetaway." It was introduced in 1964, but the name Jetaway was used on a different transmission in the '50s. It was used in the Cutlass and low-end 88 lines through 1969, I believe.

Sarum

Thanks for the info guys. My car has a 3 stage auto so the original 2 speed has been replaced at some stage. I am pretty sure it is a GM TH350 but I am going to jack the car up and get underneath to confirm and see what variant it is,More on auto trans and performance - I am going to start another thread in regard to the trans shift points and performance as I am going to be doing a bit of drag racing next month

joe_padavano

The TH350 was not released by GM until the 1969 model year, but it is an easy and common replacement for the Junkaway, er, JETaway two speed.

Sarum

Thanks for your help. The 3 stage auto must have been a big improvement over the original 2 stage. The Cutlass has been fully restored and improved so I am not surprised that it has a later model transmission.

Smitty275

If it is the original trans and is a 3 speed it is a TH400 with switch pitch converter.

aliensatemybuick

Of course a TH400 aint original to your car...but only way to know what it currently has is to take a look underneath. Also, a Jetaway will have the "PRNDL" (Park-Reverse-Neutral-Drive-Low) shift pattern whereas a TH350 or 400 will have the "PRNDSL (Park-Reverse-Neutral-Drive-Super-Low) aka "PRND21" pattern). What does your gear indicator say and does it match how many gear positions you got?

oldcutlass

There were no T400's or 3 speed automatics stock for 65.



You can have the stock 2spd shifter placard (PRNDL) with a 3 speed trans. Most people who change from the Jetaway to either T350 or T400 never change it.


You can determine the type of trans in your car by the shape of the pan. Another way to differentiate the difference is the trans mount position (t350 is in the stock location, the t400 is 6" to the rear with new holes drilled), and the T350 uses a kick down cable for passing gear, where as the T400 has an electric switch.

aliensatemybuick

Which is why I asked if the shift indicator pattern matched the...oh, nevermind.

oldcutlass

I misunderstood your comment I thought you were just talking of the indicator. Sorry

aliensatemybuick

No problemo...I probably said something else wrong anyway, haw haw!

joe_padavano

The TH400 was not factory installed in A-body cars until the 1967 model year. The ST300 was the ONLY automatic available in the Cutlass/442 line until then.

aliensatemybuick

I like the first answer best, BTW.