T90 Teardown Important Correction to Rick Stivers Guide
I have seen this come up from time to time. While you can remove the T90 reverse idler shaft to the outside of the case, it is not a good idea. Unfortunately many have done it incorrectly and ran into a lot of difficulty. Hopefully this will help some avoid the issue.
The Rick Stiver video/write up is an excellent source. There is one major mistake that has not been corrected. When removing the reverse idler shaft in a T90 it is driven INTO THE CASE. I think Rick is adamant about using something to reach in and drive it out of the case. This is incorrect. It can cause a few problems as it was designed to be driven into the case. It is easy to do when you drive it into the case as intended. It can be removed the other way but it is not correct, difficult to do and can lead to damage. ON THE T84 the shaft is driven out of the case, DO NOT DRIVE THE IDLER SHAFT OUT OF THE CASE ON THE T90.
I did write to the CJ forum about the error, but I don't think it was ever corrected. If you refer to the Borg Warner or Jeep service manuals they have the correct procedure. Here is what is written incorrectly on the Rick Stiver instructions. It is important to note this is an incorrect process. The shaft is easily driven INTO the case on a T90.
D-25. Using tool E drive the reverse idler gear shaft out the back of the case. T_90_Rebuild/ReverseIdlerShaftRemovalT.jpg (9627 bytes) (This must be done from inside the case. Caution: do not attempt to drive the shaft into the case from the rear as this can damage the shaft and the case. Remove the reverse idler gear from the case. Some people have found it necessary to use a bent piece of rebar to drive the reverse idler gear out of the case. Use as little force as you can to prevent damage. Whatever you do, don't drive the shaft into the case.)
(Here is a helpful tip. When driving out the reverse idler shaft, stand the case on its tail end. To do this, place a 3/4" deep-well socket over the end of the shaft, and place 3 more deep-well sockets around the bottom to provide good balance. Have a second person hold the case in place and drive out the shaft. This was much easier than trying to hold the case in place laying flat.)
Last edited by bmorgil; 08-04-2021 at 08:14 AM.
Reason: Add image of reverse idler and shaft
I'm into the dreaming up part of my Tornado engine build. Looking at options. Once some ideas become likely, I'd like to get your advice similar to the above correct process.
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