by Bob Doty
(HMCC Web Editor's note: One of the best things about the Web is it allows people to work together across time and geography. Dan Stern wrote to add some details to Bob's original article. I've included Dan's comments using a round symbol and italic text. You may reach Dan Stern via The Internet Slant Six Club)

Early and late transmissions

The next subject is the Big-Block 727 transmission. The Torqueflite transmission with the aluminum case was introduced in 1962 and continued to use the push-button cable operated shifting mechanism. The 1965 model cars used both the push-buttons and column mounted shifters.
  • The 1965 model cars DID NOT use pushbuttons at all. The confusion here arises from the fact that '65 cars used a dual-cable shift control system just like the pushbutton cars of '64 and earlier, but the manual valve in the valve body was changed and the other end of the cables were connected to a column or floor shifter with an overtravel mechanism for "park" (and a matching overtravel mechanism with spring in the valve body), instead of to pushbuttons.
    By 1966 all of the linkage was mechanical and the cables were gone. The popularity of the early B-body cars with late model big block engines can create some confusion. The owner wants to keep the push-button transmission and mate it to the new engine. This is not a problem if you have the original torque converter. The 1962-65 big block Torqueflite used a small spline shaft and the later 727's used a large spline shaft. The transmission parts can be retrofitted, and the small spline converters are still available from aftermarket sources. The early (62-65) transmissions also used a flanged-type output shaft, while the later used the slip-joint. Again, the early transmission may be converted, for ease of maintenance and removal.

    How can you tell if an old converter is still serviceable? Look for signs of extreme heat on the front of the hub (discoloration similar to heating with a torch), and pick it up and shake it listening for rattling or grating noises.

    I know this sounds simplistic but it is better than trial and error. don't know about you guys and gals out there, but 1 oz. of red trans fluid on the shop floor looks like 12 gallons to me.

    Thanks - Bob Doty

    Page updated November 11, 1997

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