727 Reaction shaft

[Kevineng]

I recieved a 727 torque flight (used) for my challenger, plan on installing it on my engine on the test stand. I am not a tranny guy, so excuse my ignorance. I was told, it will "probably work" but may need new seals. I want to install it, so I can play with the engine on the stand. Anyway, I was looking over things, the output shaft locks into place when in lever is in park, as I expected, I can turn the output shaft (when not in park) and the input shaft by hand, but the reaction shaft will not turn by hand, is this normal? or is something wrong?

 

[pschlosser]

The 727 transmission is hard to break. If the seller says it will "probably work" then it "probably" will.

Unless you plan to go ahead and tear down and rebuild the 727 transmission, you're gonna have to road test it to determine if the seller was right, if it leaks, and/or if any further service is needed on the transmission. Of course, you'll have to take it out again to do any major work on it.

You can test some of these things with the engine out of the vehicle on a stand or bench. But you cannot, in my opinion, test the transmission very thoroughly. You would want to road test to determine if is shifts properly, malfunctions when hot, and other key indicators difficult to do on the bench.

If you have time on your hands, and there is a wait before your engine and tranny could be installed for road testing, you can just go ahead and rebuild the 727. It may seem intimidating, but its pretty easy. Easier than an engine, I think. For some, seeing it done, or reading a book can help.

I've recommended this book to others:

Chrysler TorqueFlite A-904 & A-727 Transmissions: How to Rebuild (Workbench How-to) by Tom Hand​

Amazon.com

Once rebuilt, she can sit until ready for road testing with some level of confidence it will work right out of the gate.

 

[rogue]

i agree with pschlosser... rebuild it while it's out. I also find it easier than an engine and just follow along with the instructions It does require a few tools you may not have around though... clutch drum spring compressor, snap ring pliers, bushing drivers... but they're not overly expensive. Pump can be removed with a 2x4 and some threaded rod. Worth considering for sure.

 

[Kevineng]

Ok, thanks. That's the long term plan, rebuild it while its out, rest of the car has a long ways to go too, but for now I need it on the stand to get engine running and see if that will need a rebuild as well. Maybe I'll try myself (might be fun), but like you said, I dont have the specialty tools. What have I got to lose, right? We'll see.

 

[Tig]

I recieved a 727 torque flight (used) for my challenger, plan on installing it on my engine on the test stand. I am not a tranny guy, so excuse my ignorance. I was told, it will "probably work" but may need new seals. I want to install it, so I can play with the engine on the stand. Anyway, I was looking over things, the output shaft locks into place when in lever is in park, as I expected, I can turn the output shaft (when not in park) and the input shaft by hand, but the reaction shaft will not turn by hand, is this normal? or is something wrong?

The reaction shaft doesn't turn, it's fixed and part of the stator. Pic below is for clarity (the outside "tube" is what you're referring to I'm guessing)
I'm no expert but I do my own rebuilds after a racer helped me repair mine trackside, prior to that I never used to touch them. They aren't bad to do and are sort of "modular" on assembly and dissasembly. I have about 4 books on the subject, they helped.
The 'box I'm using now I had behind my 950+ lb/ft 655ci engine and survived it with no issues, it's been behind my 900hp 580 motor for a while. The 655 is scheduled to go back in late next season.
Me, I'd check for debris in the trans pan and take if from there. HTH's

 

[Xcudame]

It will be fine for hooking to your engine on the test stand. Once you get your engine broken in, you can rebuild the the transmission. I like the two books below. Both have a wealth of information.