I took my transmission completely apart to rebuild it. When i put it back together again I did not completely understand the interlock system. when I did realize what it did, I decided to remove the interlock system. so I pulled out the interlock rods and the slider locking thingy. What I did not realize until later is that there is a half moon key in a slot in a shaft way down in there. Its the first shaft you put in during reassembly. Anyway if you do not also remove this key you have a crazy combo of shift pattern to get the 4wd engaged I think it is something like it has to be in low range, and low gear to engage the 4wd. And after it is in 4wd you can shift into any gear as long as you do not shift out of 4wd. once you shift out, it has to be in the one special combo to get back into 4wd. I tried every possible combination of gears and wrote it down and can still hardly understand it.
I just use 2wd and it shifts normal but 4wd is there if it is needed. My advice is either leave it all in or take it all out. But with only some of the parts removed its even more complicated than normal.
It says in the operators manual how it shifts. This is from memory but it is something like it has to be in 4wd for all low range and, hi 1and 2 and reverse, optional in a couple of other gears but must be in 2wd in the higher gears.
If some one has the book handy please correct me if I am wrong. I will look it up when I can and make corrections as necessary.
Thats what I know about interlocks. I think I may still have the rods and slider lock around somewhere.
Henry