904 trans

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Johnny71dusty

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I have a few 904 in my shop. All from satellites and challengers . Will they fit into my dart ? My dart needs one and wonder are they they same ?
 
I have a few 904 in my shop. All from satellites and challengers . Will they fit into my dart ? My dart needs one and wonder are they they same ?

If they are all OEM Challenger & Satellite, the only differences I can think of would be LA vs /6 bellhousings. I believe /6 had some lighter duty internal components.
Physically they will fit, but very early 904s and late 70's-'80's lock-up 904s would be different and can cause interchange problems.
 
If they are all OEM Challenger & Satellite, the only differences I can think of would be LA vs /6 bellhousings. I believe /6 had some lighter duty internal components.
Physically they will fit, but very early 904s and late 70's-'80's lock-up 904s would be different and can cause interchange problems.
My dart is 360 that I’m trying to put one of my other trans into it . But I know with manual trans the tail of the trans is different t for A bodies.
 
I purchased this book because I plan to rebuild my 904. It has a chapter up front that goes over how you can identify the differences in each variation year by year. I would definately recommend it. When I was in High School secondary vocational auto class I thought I rebuilt 12 727's that year. I had never heard of a 904. After getting this book, I realize I probably rebuilt a mixture of 904 and 727 without knowing it. Here it is. Good luck
upload_2022-6-27_7-40-18.png
 
The LA 904 will work, some of the /6 904's had a lower first gear & 4 pinion planetaries. I pulled those & installed them in my transmissions.
 
904 passenger car tailshafts are the same. There may have been some short tailshaft versions in trucks.

As for the low gear 904s, they started that around the same time as lock-up transmissions and it included V-8s. (Late 70s - early 80's.) But you have to know what to swap, especially if it's a lock-up converter version.
 
I just want to throw in a trans and go but all my working trans I pulled from cars were e & b body. so wasn't sure if a A body 904 was the same length . dot get why they are if the manuals all have different tail lengths why the autos dont but im happy for that answer. MY dart has a 360 does have a 727 behind it , but I dont care what I put there I just want to choose my best trans that will work which is probably the 904 I took from a good running satellite last year. just didnt know it would fit same
 
AFAIK;
>ALL passenger-car 904s were short tails just like the A833 short tails; even use the same driveshafts. and
>ALL p-car 727s were Long tails, and
>you can swap these transmissions around, because the rear mount is in the same place. But, of course;
> the driveshaft lengths are different, as are
> the convertors and the flex-plates.
> you will have to swap whatever shifter mechanism and KD rods that came in your car, onto the one being swapped in.
>>However; the governors may or may not work properly, depending on what gears you have, and what gears were in the car that you pulled the trans from. AND you should swap over whatever Speed-O gear is in your Dart now, assuming it is correct, clocking it correctly in the replacement trans.AND if you have to tug the cooler lines around, then when you're done, you gotta make sure they don't rub or vibrate against anything that they ought not to. And finally; the dipsticks are matched to the dipstick tubes, and usually, the B-body stuff is longer than the A-body stuff, so you gotta match them up.
>Don't forget, if you have to install a convertor, it has to go into the trans first. It has to index in three places, namely; the pump, the stator, and the input shaft. When finished, the TC will be rearward from the engine to BH jointline; and after bolting the trans to the engine, you will have to pull the TC OUT of the trans around 1/4 inch to meet the flexplate. The TC may fit onto the flexplate, only one of four ways so mark it before you mount the flexplate to the crank.This just makes it easier to find later.
Your TC will have to be balanced to the 360 crank, so if it has weights welded on and did not come off a 360LA, then they will be in the wrong place.
Happy HotRodding
 
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