I have been getting a lot of PM's lately about this mod and how it works and fits together; I thought I would post the details here for everyone as I recently rebuilt my diffs after inspecting them.
This should be read in conjunction with Post #26...a lot of the questions have been what happens from here and how does it fit together.
Traxxas Part #5454
I hack sawed the threaded end off and then grinded down so that the drive axial was a length of 22.25mm. I also chamfered the sharp edge so it was nice and smooth fit in the diff cup.
When installing in the diff, this is what I did.
I fitted the pin which I took from LOSI LOSB3540 Differential Outdrive Set...(I only needed the pin for the traxxas drive axle); I then put 1 x 6mm shim and the o-ring.
This is how it fits to the spider gear. Their is a recess in the back of the spider gear to accommodate the pin.
In the view below you can see the stub axial protruding slightly out of the spider gear...this is the side I cut the tread off and chamfered to remove the sharp edge. If you insert the Losi drive cup it protrudes something similar.
The end result...this is what it looks like when the spider gears and internal crossbars and spacers; diff cup and ring gear are assembled together .