AWD vs. 3WD / FWD vs 1WD

[LarryIII]

SVXY has, what I believe, is a serious problem. For the last few weeks I have been hearing a high pitched whine that sounded like gears meshing. I happens at speed 35mph and up getting higher pitched the faster that I go. I does not happen when the car coasts, only when it is given gas. I thought that th esound came from the rear.
Two weeks ago, I put the car up on ramps and checked everything first the rear then the front. everything seemed tight and okay.
Early this week my buddy returned my second set of jackstands (he's restoring a '68 Vette). Yersterday morning I put the car on the jackstands with all the tires off the ground and fired it up. All the wheels spun except the right front. Using a long rod I stood on the right side, outside the car, and bipped the throttle. The right front wheel still did not spin.
I put the FWD fuse in and got the same results (1WD).
I did not get under the car. so I don't know if it's the outer or inner (God forbid) passender side drive shaft.
If anyone here has experienced this malady, please post some direction or suggestions.

I was down yesterday after discovering this because SVXY is my daily driver. But today I'm OK and am 85% sure that this problem can and will be fixed. I'd hate to use SVXY as a parts car.