Bronchole
Bronco Guru
How to seal a Dana 20, Step-by-step
In the following posts I have compiled a comprehensive list of the points where the average Dana 20 manages to sprout leaks and how to fix them. This list and their fixes came from a collaboration of several people and will be a live document that will continue to be updated as people give their input. For the convenience of the reader I have provided links in this first post to the individual sections that cover the particular problem area.
Please, as you use this thread if you notice typos or have an idea on how to improve it post up a reply to this thread. I will almost certainly incorporate what you suggest, no matter how long it has been since it was last updated.
Follow the links below to the particular leak point you are chasing:
- Hardware (see post #2)
- Trans to T-case adaptor housing (see post #3)
- Trans output shaft to Adaptor seal (see post #4)
- Rear output shaft to rear output yoke (under the nut) (see post #5)
- Rear output yoke to rear output housing seal (see post #6)
- Speedometer connection to rear output housing (see post #7)
- Shift rail seals, shift rail bolts, rear shift rail caps (see post #8)
- Rear output housing to T-case housing (see post #9)
- Idler shaft to T-case housing (see post #10)
- Front output shaft to front output yoke (under the nut) (see post #11)
- Front output yoke to front output housing seal (see post #12)
- Front output housing to T-case housing (see post #13)
- Front bearing preload cover to T-case (see post #14)
- Drain plug (see post #15)
- Inspection cover (see post #16)
Useful links:
Here are some other useful links when working on your Dana 20:
- Dana 20T rebuild small.pdf
- Dana 20J manual.pdf
- Novac: Rebuilding the Jeep / IH Dana 20 Transfer Case
- A good post on removal and installation of a Dana 20 in a Bronco
- xcntrk write up on modifying the shift rails
- Bronchole's explanation of how ground shift shafts work, and don't work
- Post#32 in this thread has some great pictures of shift rail modifications
- A good thread on twin sticking with shift rail modifications
- xcntrk's explanation of a fool proof interlock scheme with a great video.
- Discussion on preloading rear output shaft bearings (a possible solution to popping out of gear)
-
To any and all using this article, please let us know how it worked for you. Even if you don't have any further input it will help to let others know that the article works and keep this from being too old to show up at the top of searches.
Dan AKA Bronchole
PS,
I would like to thank Lilthom, Viperwolf1, 70_Steve & BwoncoHowie (in order of their posts) for their help in the initial composing of this tech thread. With their help, part numbers, links and suggested procedures I was able to put this together with minimal effort. Thank you very much guys.
Additional editing provided by: Andy canary28,
Added info from Viperwolf1 from post#24
Added tags from canary28 from post#55
Added "useful links" section as a thought after reading Canary28's post#61
Tags (terms people can use to find this thread): X T x-case t-case transfer case transfer-case leak leaks seap seaping seaps seep seeps seeping rebuild rebuilt rebuilding sealing seal reseal re-seal gasket seals gaskets dana 20 drip dripping adaptor housing intermediate
In the following posts I have compiled a comprehensive list of the points where the average Dana 20 manages to sprout leaks and how to fix them. This list and their fixes came from a collaboration of several people and will be a live document that will continue to be updated as people give their input. For the convenience of the reader I have provided links in this first post to the individual sections that cover the particular problem area.
Please, as you use this thread if you notice typos or have an idea on how to improve it post up a reply to this thread. I will almost certainly incorporate what you suggest, no matter how long it has been since it was last updated.
Follow the links below to the particular leak point you are chasing:
- Hardware (see post #2)
- Trans to T-case adaptor housing (see post #3)
- Trans output shaft to Adaptor seal (see post #4)
- Rear output shaft to rear output yoke (under the nut) (see post #5)
- Rear output yoke to rear output housing seal (see post #6)
- Speedometer connection to rear output housing (see post #7)
- Shift rail seals, shift rail bolts, rear shift rail caps (see post #8)
- Rear output housing to T-case housing (see post #9)
- Idler shaft to T-case housing (see post #10)
- Front output shaft to front output yoke (under the nut) (see post #11)
- Front output yoke to front output housing seal (see post #12)
- Front output housing to T-case housing (see post #13)
- Front bearing preload cover to T-case (see post #14)
- Drain plug (see post #15)
- Inspection cover (see post #16)
Useful links:
Here are some other useful links when working on your Dana 20:
- Dana 20T rebuild small.pdf
- Dana 20J manual.pdf
- Novac: Rebuilding the Jeep / IH Dana 20 Transfer Case
- A good post on removal and installation of a Dana 20 in a Bronco
- xcntrk write up on modifying the shift rails
- Bronchole's explanation of how ground shift shafts work, and don't work
- Post#32 in this thread has some great pictures of shift rail modifications
- A good thread on twin sticking with shift rail modifications
- xcntrk's explanation of a fool proof interlock scheme with a great video.
- Discussion on preloading rear output shaft bearings (a possible solution to popping out of gear)
-
To any and all using this article, please let us know how it worked for you. Even if you don't have any further input it will help to let others know that the article works and keep this from being too old to show up at the top of searches.
Dan AKA Bronchole
PS,
I would like to thank Lilthom, Viperwolf1, 70_Steve & BwoncoHowie (in order of their posts) for their help in the initial composing of this tech thread. With their help, part numbers, links and suggested procedures I was able to put this together with minimal effort. Thank you very much guys.
Additional editing provided by: Andy canary28,
Added info from Viperwolf1 from post#24
Added tags from canary28 from post#55
Added "useful links" section as a thought after reading Canary28's post#61
Tags (terms people can use to find this thread): X T x-case t-case transfer case transfer-case leak leaks seap seaping seaps seep seeps seeping rebuild rebuilt rebuilding sealing seal reseal re-seal gasket seals gaskets dana 20 drip dripping adaptor housing intermediate
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