Moses,
I am starting the Twin Stick Dana 300 rebuild to address the jumping out on down grades issue. This unit had major work about 16K miles ago when a 4:1 gear kit was installed by a pervious owner. The Odometer now has 282K miles and most likely is was a California commuter Jeep in its early days (266K miles 1985 - 2003). This may be an interesting journey.
First look don't seem too bad.
Clocking Ring and Input Shaft.
Clocking Ring Gasket was not salvageable. Not real sure what its function was as it is not a water or oil seal.
Input Bearing Unit Removed.
Even though I plan on installing a master kit, the input gear/bearing assembly looks and feels so good, I am reluctant to take it apart. Moses, you may have some input on that.
Now for the bad news.
The front shift fork was binding on the shift rail so tight that it took a couple of hours to separate the two. Once I finally got them apart, my nerves were completely shot and set them both to the side to be inspected maybe tomorrow.
Centered in this picture is the rear output gear. On the right half of the rear output gear is the High Range side of the gear showing quite a bit of wear. If I were guessing, this gear is the original with 282K miles. To the right you can see the input gear that is in good shape. Not shown, is the Low Range gear that would normally be to the left in the picture, and it looks as good as the input gear.
The sliding collars are most likely original as well. However the wear was not as pronounced as the rear output gear, but still more wear than I would like. Also the collars had been swapped around by the previous builder for the best fit.
Even though this Rear Output Gear was not causing trouble, I am not comfortable with it and have ordered a replacement along with 2 shift collars.
Had my wife steading the case while I was pressing out the bearings. One of them let go with a good pop and she was sure we had broke something. LOL.
Moses, you might want to jump in with this popping out issue. I will pay very close attention during installation to linkage binding.
I am already planning on installing the stiffer JB Conversions detent springs. New shift collars can't hurt. Is there any thing about the shift rails you can thing think of?
William