A904 transmission swap

tookie

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Can some one help me. I have a 1973 dodge polara custom. Has a 318 that had a 904 in it. Had to pull the old one it was shot. I just got one from a guy out of a 70 dodge dart. $300 bucks. Everything looks the same. Do any one know if I'll be able to go straight in with it or if there's a difference in the. I can't really tell. I know the polara is a c body but does that make a difference will the 904 from the dart still work
 
Thanks so much. It has me worried. Didn't want to be wasting money and still looking
No problem, just a side note there could be infernal differences inside the transmissions. Some were standard and some were HD depending on the vehicle. That will not effect if the trans can be installed and used in your car. If you get the part numbers off the pan rail of each transmission and post it up here we can check.
 
No problem, just a side note there could be infernal differences inside the transmissions. Some were standard and some were HD depending on the vehicle. That will not effect if the trans can be installed and used in your car. If you get the part numbers off the pan rail of each transmission and post it up here we can check.
Ok sure will
 
Check the kickdown lever on the transmission. If they are different lengths, use the one from your Polara. A body uses the 3 rod bellcrank kickdown system with the shorter lever. C bodies usually use the 1 rod system with the longer lever. If you use the wrong lever the ratio won't be right. So you should be using the longer lever.
 
Check the kickdown lever on the transmission. If they are different lengths, use the one from your Polara. A body uses the 3 rod bellcrank kickdown system with the shorter lever. C bodies usually use the 1 rod system with the longer lever. If you use the wrong lever the ratio won't be right. So you should be using the longer lever.
Great point.
 
In 1971 they went to part throttle kickdown, if you install a 1970 trans you won't have that, not the end of the world, but it is nice to have. A & A Transmission has a kit to add to the 70 and earlier transmission.
 
What do you mean

If you're asking about WHAT a "part throttle kickdown" IS, that means the kickdown will occur just when you push the throttle open ENOUGH for it to kick down into a lower gear, as opposed to the older kickdown which only works when opening the throttle ALL THE WAY. My 1966 727 came with a strictly WOT kickdown, but installation of a modest shift kit permits it to kick down with the throttle open just about 80%. In urban environments, that has merit.
 
Using the same converter or the one from the other? Rebuilding these is pretty easy
They are, changing out the clutches and bands are simple but you better know what you are doing changing seals or you can damage them, know how to recognize bad bushings, how to install them if needed, inspect the sun and planetary gears, and check your end play. Yes pretty simple unless you miss something and then you do it all over again.
 
They are, changing out the clutches and bands are simple but you better know what you are doing changing seals or you can damage them, know how to recognize bad bushings, how to install them if needed, inspect the sun and planetary gears, and check your end play. Yes pretty simple unless you miss something and then you do it all over again.
Really, they are easy to rebuild if you have a hobby garage. Nice 14 part tutorial on youtube and the one book that gives inch pound torque specs. You can miss something on everything you rebuild and have to do it over again. Carbs, fuel pumps, power steering pumps. These things are not magical and the shop manuals explain the procedures in detail. Just follow the tutorials and be exacting on the tolerances and clearances and don't work on it when tired. Seals are nothing to put in. Bushings the same. Tools for free from ORielys if you need them. Some where at some time some guy who never did something had to do it because they had no other choice. Don't except failure on your end and be diligent. Accept the challenged. A good trans rebuild kit is 200 bucks and that is with top shelf clutches. I have tossed more money away at beer learning to rebuild motors back in the day.
 
Really, they are easy to rebuild if you have a hobby garage. Nice 14 part tutorial on youtube and the one book that gives inch pound torque specs. You can miss something on everything you rebuild and have to do it over again. Carbs, fuel pumps, power steering pumps. These things are not magical and the shop manuals explain the procedures in detail. Just follow the tutorials and be exacting on the tolerances and clearances and don't work on it when tired. Seals are nothing to put in. Bushings the same. Tools for free from ORielys if you need them. Some where at some time some guy who never did something had to do it because they had no other choice. Don't except failure on your end and be diligent. Accept the challenged. A good trans rebuild kit is 200 bucks and that is with top shelf clutches. I have tossed more money away at beer learning to rebuild motors back in the day.
Just trying to make a point to do your homework and know what your limitations are. Those are great videos. I have seen more than one guy change the clutches and not do anything else and then wonder why their trans craps out again after a couple hundred miles.
 
Just trying to make a point to do your homework and know what your limitations are. Those are great videos. I have seen more than one guy change the clutches and not do anything else and then wonder why their trans craps out again after a couple hundred miles.
Only limitations a person has is the ones they set on themselves. I learned that decades ago in the Marine Corp. It just might take more time to learn what you think is impossible o do. Other people do it so why can't I ?
 
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