I've been trying to locate the sound for a couple weeks with no real luck. I removed the skids the other day and tried the "long screwdriver" technique you mentioned (in my case, a long 3/8" extension) but failed to find anything that seemed way out of line. I removed the a/c and ps belts - whine was still present. Based on that, I don't think it's the a/c idler pulley which is what I was hoping for. Yesterday I cranked 'er up in the driveway with the windows down and spent a couple minutes listening to the engine at different rpm in different gears. To my disappointment I noticed that the sound, while present in all shifter positions, changed pitch slightly when in R or D. I haven't had anyone rev the engine for me while I was under the vehicle so I could listen to the transfer case or transmission but this is beginning to sound (no pun intended) a lot like a tranny/torque converter issue. I hope I'm wrong.
