79 and newer 727's

[-Boosted-]

I read somewhere that 79 and newer 727's all had lockup torque converters. Is it possible to convert these transmissions to accept a non-lockup converter? If so, what all is involved besides the converter?

Thanks in advance,
Bill

 

[Bobzilla]

They do not all have lock up converters. I currently have one in use from an 80s era D100 truck that is same length as a car, no lock up converter, and has extra strengthening ribs on the tail housing. The strengthening ribs do get pretty close to the torsion bar crossmember on an A-body, but mine does not make contact in a 75 Dart sport.

 

[-Boosted-]

Just found this using Google....

• "You can identify A-727s as being the 1978 and newer lockup units by looking at the input shaft of the transmission. If the shaft is machined smooth for the last half-inch of the shaft, that transmission was equipped with lockup. Non-lockup transmissions are splined all the way to the end of the input shaft."

Sounds like at a minimum, (if what I have is a lock up style) the input shaft will need to be replaced.

 

[Bobzilla]

The valve body and I think the pump (going off memory) are also different, with different passages. It's cheaper to get a non-lockup core, since you will be sourcing the swap parts anyway. Of course, if it's an all out build, you would be replacing those parts anyway so it would not matter which one you started with.

 

[-Boosted-]

The valve body and I think the pump (going off memory) are also different, with different passages. It's cheaper to get a non-lockup core, since you will be sourcing the swap parts anyway. Of course, if it's an all out build, you would be replacing those parts anyway so it would not matter which one you started with.

Good points. Trying to get in touch with my builder to verify what I dropped off and if he can build it to my specs.... lol

 

[Locomotion]

 

[rumblefish360]

Well! That solved that one with a picture pretty well!

 

[-Boosted-]

Thanks for the help guys. My builder confirmed he's building me a non-lockup style.

 

[71Demon528]

In addition to everything listed above, the front pump stator support has to be matched to the input shaft and hub, which I’m sure your trans guy knows. 78 and newer 727s had 3 sealing rings compared to pre 78 had only 2. The stator support will have 3 holes and 3 balls if it’s lockup, if it’s non lockup it will have 2 balls and 3 holes. Attached is a photo of my stator support which is non lockup. As you can see there are 3 holes and only 2 check balls in the holes.