The VC or center diff controll coupling assembly as Toyota calles it, is what I think went bad on the old t-case. I did some tests with the VC. I put the VC on the out put shaft and it turns with some effort. I bolted a 3ft bar to it and truned it as fast as I could. I couldn't turn it very fast as there is a lot of resistance but not more than an exercise bike on a very hard setting. I couldn't get it to lock up ( it made me lock up turning it as I am not in shape ). I then got the torch and heated it up as I turned it, when it got hot to the touch, it locked up. When it cooled, it unlocked.The VC is on the rear output shaft. I removed the VC fron the t-case. I could turn the input shaft and both output shafts would turn just like a open diff would. So removing the VC and driving should be a problem unless it us also used as a shim. It didn't look like it is when I looked at it.
I don't know for sure how the VC is suppose to work but this is my theroy:
When driving and all wheels as going about the same speed ( do to turning) the power can go to either the front or rear axle as the t-case is just like a open diff.
When one axle starts to spin, the VC will heat up and lock ( remember there is resistance/friction in the VC and friction = heat). When the VC locks, the diff part of the t-case is bypassed and both output shafts will turn ( like when the center diff is locked).
The other theroy is that only a certin amount of resistance that the VC can spin. Any thing more than that, it semi locks and turns both output shafts.
When I remove the t-case I will first remove the front drive shaft and do some more tests.
kurt
I don't know for sure how the VC is suppose to work but this is my theroy:
When driving and all wheels as going about the same speed ( do to turning) the power can go to either the front or rear axle as the t-case is just like a open diff.
When one axle starts to spin, the VC will heat up and lock ( remember there is resistance/friction in the VC and friction = heat). When the VC locks, the diff part of the t-case is bypassed and both output shafts will turn ( like when the center diff is locked).
The other theroy is that only a certin amount of resistance that the VC can spin. Any thing more than that, it semi locks and turns both output shafts.
When I remove the t-case I will first remove the front drive shaft and do some more tests.
kurt