CY & CX 400THM: differences & similarities

[Chevy454]

Using a 1969 "Hydra-matic Production Parts" list, I charted the differences and similarities between the "CY" & "CX" automatic transmissions, as well the difference between the "CY" & "CX" and the standard 400 automatic transmission.

[Mr70]

That's Real Nice work Rob.

[SS427]

Very nice Rob and very helpful!

[CamarosRus]

Rob, To help the inept, like myself which vechicles used a CY or CW and what is diff between them (CW/CY). My ORIGINAL 70 Z-28 (bought NEW) with column shifted T-400......may I assume this had either of the two???
Thanks, Chuck

[Mr70]

For the year 1970:
*TH400 CY Trans. was coded for the LS6 Chevelle,& Corvette LS5.
Higher-shift point and stronger bands & springs.I believe a thicker shaft as well?
*TH400 CW Trans. was coded for the L78 Chevelle-Nova-Camaro,& LT-1 Camaro-Nova.
*TH400 CR & CS Trans. was coded for the LS5 Chevelle-Monte Carlo,& Corvette w/Transitorizied Ignition.
*TH400 CF Trans. was coded for the L34 Chevelle-Camaro-Nova.
*TH400 CK Trans. was coded for the 300HP 350cid Corvette.

[YENKO DEUCE REGISTRY]

Chuck, the comparison is between the CX vs. the CY, not the CW version. The CW was used in the L78's, LT1's etc...

[Chevy454]

Ray Morrison sent me some more 400-THM info. It was an application chart for 1969, so I went ahead and ran it through Excel so it's easier to digest...

[Chevy454]

Here are some detailed pictures from a 1968 CY THM400 trans, courtesy of Tommy K and the Super Car Workshop...

[Chevy454]

VIN...

[Chevy454]

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