First Time 904 Rebuild?

[65Valiant310]

How difficult?
I ask because I am going to purchase an extra 904 trans to rebuild, yet wanted to know if this was better left to the professionals? My current one is slipping/on its way out and Id rather have a stock built backup.
I have the TCI technical manual for the A904, yet wondering if this would be enough.

 

[70aarcuda]

904 are pretty easy...they are pretty much like a 727 but everything is smaller...

besides the manual...you will need snap ring pliers...various sizes.....

you will need to compress the front clutch pac to remove the piston to replace the lip seals on it...

and you will need to remove and replace bushing on the pump...front drum and tail shaft, those need bushing drivers ...

you can take the individual part to a trans shop and let them replace the bushing for you...and the same with compressing the front clutch pac...

 

[Dakota_Don]

if you can read a manual, or even get a vid the 904s are simple.. you can make the tools to take the cluch packs apart ect.. go to scribs.com and look for a online manual or purchace a vid.. the vids are pretty kool IMO..

the 904 is simular to the 727, even the phord trans are simular..

 

[grimreaper]

Two books you might want to look at are the ATSG TMTF A-727/A-904 manual and a book called Torqueflite A-727 Transmission Handbook by Carl H. Munroe. With those two you should be able to get the job done quite easily. The second shows you how to make some tools that are needed and gives some nice tips. I think the books make the job appear harder than it is but I learned from tearing 'em apart, replacing necessary parts and reassembling back in the old days......then I got the books later and learned how to do a real rebuild and a bit about how they actually work. Otherwise keep things CLEAN and organized. You will find it to be a straightforward job. A good source for parts is www.bulkpart.com.

 

[65Valiant310]

Oh the book I have is the ATSG one, not TCI
Thanks for the info all