I found a 904 tranny out of a 65 Dart GT. Would I be able to use this to replace my 727TF that is currently in my 81 Mirada?

 

You could, it will bolt right up. It will be a step down as the 727 is far superior and stronger than the 904.

 

I do not know if the 727 needs rebuilding. I had a friend driving the car for the last year and he told me it won't go into reverse until it warms up. I can get it rebuilt for around $650 but I am going to change the fluid and filter before I try that. The guy who has a tranny shop told me to use GM's Limited Slip Differential Addative to help it shift better and smoother. It really worked great when the lock up torque converter started shuttering. He coud have just taken my money but he doesn't think it needs a rebuild. His advice was to service the fluid [not flush] ,restore the lost fluid with Lucas Oil and use the addative from GM and it should work fine. If not we can rebuild it.

 

I have had 3 different trannys in my Roadrunner and they all did that in reverse. It would go into reverse cold but it would take a couple seconds in that gear before it would actually kick in and move. I have found it to work better if I leave it in neutral for a few seconds and then put it in reverse and then it grabs and goes right away without the lag from putting it straight into reverse.

 

Moe in Wichita,KS

on the older mopars the trans would not go in reverse when the trans oil filter was cloged. why rev. and not forward gears? because rev. runs the trans. line pressure to 350 psi. forward gears to 100 200 rsi. the higher pressure takes more volume of oil that the cloged filter cant pass. but i dont know about the newer mopars

 

904 is basicly a 727 with an overdrive but the overdrive is the weak link. your better off with the 727

 

There would be a ton of linkage/cable shifting issues here. It would be a BEAR to adapt that 65 trans to a 1981 vehicle.

If the Mirada is just a cruiser ... you would be BETTER off with a 904 .. if you could find one that would bolt-up.