Tranny/Rear end prblems?

[cdnstudman]

Hi all, I recently traded a broken big screen for a 93 Explorer Sport w/4.0L V-6 in it. It runs great, but the 4X4 wasn't working so I removed the electronic transfer case shifter motor, and turned the lever with pliers. The 4X4 works, great! well thats what I thought, now I get a clunking when I downshift (in 2 or 4 WD), and can't tell exactly where it comes from. I am pretty sure it is in the transfer case/tranny/rear end cause it doesn't do it if the clutch is in while braking. This problem is only on downshifting, acceleration is not a problem. My first thought was rear end, so I drained it, cleaned it, and replaced fluid with a mix of 85 gear oil and ATF (hope this was okay, buddy at auto store told me too), but still no change. I was thinking of draining transfer case and tranny, but to honest I have never changed fluids in a manual tranny before, so have no clue what fluid to use in the? So if you could tell me what fluids to use, and if what I put in the rear end was okay (seemed odd to me having to mix fluids). Also any help in what may cause the clunking would be great too.

Thanks