A tale of two transmissions

[TwistedShifter]

This is my first formal post so go easy on me. I have a '73 SE Charger and it currently has a 318 with a A904 with a funky high gear/reverse issue. It may be seals or the clutch pack. IDK. I'm on a tight budget and want to get this on the road and stop sitting. It may get an upgrade with more performance down the road, I do have a performer and eddy carb on it and the linkage was corrected to allow it to work right. I found a A727 with a 340 Converter for only 250.00 from a buddy. I know it would bolt in and think the drive shift may need to be shortened to complete the swap. Should I just spring for the A727 and bite the bullet and upgrade it at this point? I'm really leaning towards this direction, but need a nudge.

[Dino]

If the 727 is in good shape and just sitting there then I would probably install it.  The 904 looks to have some clutch issues and you can always fix it while still having the Charger to drive.  I'd keep the driveshaft as is and with the 904.  I'm sure you can find a 727 driveshaft somewhere.  

[Cooter]

Remember you will most likely need to swap driveshaft as well. 727 is longer. YES, go for the swap unless you want to swap to a BB then, you have no option with the 727 as mandatory.

[TwistedShifter]

I do believe there is a different yoke between the 2 transmissions? Would a 518 yoke work too if I cannot find a 727 yoke? Trying to keep my options open and start hunting for parts too. I found out the transmission has a shift kit and a deep pan too. Sound like I better jump on this like a hobo on a ham sandwich.

[John_Kunkel]

If money is the issue it'd be lots cheaper to just repair the 904; remember, it doesn't need to be completely overhauled just to fix the front clutch issue. If you can pull the trans yourself, cheaper yet.

[TwistedShifter]

I can pull the transmission at a buddies full service shop and use the equipment to keep costs down. My luck would be the A904 needs more work and cost more to repair than an A727 ready to go, outside of the couple of pieces needed to complete the swap, which sounds like a yoke and driveshaft. The transmission comes with a neutral balanced torque converter so there is a savings right there and I figured someone needed a rebuildable core with a new converter to offset the costs of the swap. I just got a bonus that the old lady don't know about that should cover me to get it done. My luck with the A904 and money spent so far I should have gone with an upgrade a while ago. Things seem to be falling into place.

[Troy]

I think I gave away a 904 last year - couldn't sell it! If you need to get on the road then I'd just rebuild the 904. You don't *need* to upgrade today which means you don't need to fight with any odd incompatibility issues either. If the 727 is guaranteed in some way then you might be ok - but you still have to sort out the drive shaft. I don't remember if the linkages or cooling lines are any different.

Troy

[Scaregrabber]

I'm not a guy to rebuild weak parts when HD stuff is available. I would do the 727 now. I really drive heck out of my cars though. Dana 60's, 18 spline 4 speeds, 727's, big u-joints for me.

Sheldon

[John_Kunkel]

The slip yoke and the driveshaft aren't the only items than can befuddle you on a 904-727 swap. Shift linkage and TP linkage are different too.

[flyinlow]

I think 904 's have a 2.77 first gear compaired to a 2.45 first gear in a 727.  Helps get a 4000 lb car moving. One plus for the 904.

[John_Kunkel]

Depends on the year, the low gearset didn't arrive until '80 in the 904.

[TwistedShifter]

I bit the bullet and took it to be repaired at a friends shop, a great price, the car drives like a dream. The transmission needed the following:

• R&R Clutches
• Rear band
• Trans Go Shift Kit, since he was going to be in that area any way
• and replaced the direct steel plates

I am completely satisfied and next phase is stripping the interior and getting ready for paint and body.