Help identifying 904 low gear set components

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mshred

The Green Manalishi
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So im looking to swap a low gear set into my 71' 904 transmission, and I know I should be able to get the parts I need from my local transmission parts house. However, I am not sure which variety of the parts I need. I know anything later than 82' with a 904 variant or A-500 should have what I need. I also know (or believe I know) that the parts necessary are the sun shell, the sun gear, the front planet(I already have a 4 pinion steel front planet that I was hoping could work), and the ring gear (with hub?). Problem is, in the parts catalogs there are so many options im not sure which to go with.

For example, for the same model years, sun gears are offerred in overdrive straight, 22 degree angled and 15 degree angled teeth...or I can get a sun gear and shell together, but both are for the same model years and described as large planet, 5" OD ring gear, with either 6-1/8 or 6-3/8 OD at lugs.

I have no idea what I need here....Don't know who has done this before sourcing the parts from a warehouse instead of from an actual transmission, but here is the catalog I am using, and all the parts seem to be on pg#308 of the catalog.

[ame]http://www.kingomatic.com/documents/KOM_Automatic_Trans_Catalogue_2008.pdf[/ame]

If anyone can give me a hand that would be very very much appreciated

Thanks!
Matthew
 
Bob, I was always under the impression that parts from the OD units would also work for the low gear swap into non OD transmissions...unless I am wrong?
 
I was up way to early and looking at the parts in the od housing, my mistake. maybe this will help. the sunshell gear is bigger on one side than the other so my best guess is the od parts would be the bigger diameter ones. if I recall right they were listed as a complete set on that page also. you might give cope a call and discuss what to measurements to look for.
 
I was up way to early and looking at the parts in the od housing, my mistake. maybe this will help. the sunshell gear is bigger on one side than the other so my best guess is the od parts would be the bigger diameter ones. if I recall right they were listed as a complete set on that page also. you might give cope a call and discuss what to measurements to look for.


They do sell the sun gear and shell together, both say for large planet, but again with different OD lugs

But as far as the actual planet and ring gear go, that is still confusing as well... lol
 
ok i'm on my first cup, looking at the parts list they have the 38t-28t sungear (#612F) unavailable (NA). that should be the sungear you would need to get the lower first gear. the 904 you will be looking for the gear set from is a 999 and if I recall correctly that is around mid 80's.
 
The low gear set shell will have a larger sun gear on the inside and a smaller one on the outside. The planetary sets will only fit the proper sun gear. All the stock ones I've seen are the same angle. Some have 4 planetary gears and others have 3, some have aluminum carriers and others steel, we prefer the steel ones for the strength. The ring gear and the planetarys should be one unit held together by a snap ring. They will fit in any 904. You may want to look for the 5 clutch front drum also, this is the weak link in these transmissions, you do need the proper front pump from a non lock up unit to make it fit. All these parts can be found in some 999's, but from the outside they all look the same. The gear sets have been around since the early seventies. I'm not sure if the gears from the O.D. units will work.
 
.....................I was under the impression that 1972 or 1973 904s already had the low gear set......up here anyways......I've seen 1975 up 904s that came off 360s have 4 or 5 clutch front drums......kim...........
 
Ordered everything I needed for the low gear swap plus clutches, steels, gaskets, seals, etc to rebuild from A&A Transmissions. Came to under $600.00 shipped. Why go through the headache. Call them and let them put it together for you. Just my .02
 
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