I bought my 95" Pathfinder SE (Automatic) about 6 months ago. The first time I put it into 4WD I had trouble getting it to disengage. The lever shifts fine and I made sure to reverse at least the length of the truck, but after driving about a half mile I heard this horrible grinding noise, but when I slowed down to about 5MPH it disengaged. But a few miles down the road it did it again. This went on for a few more times before it finally stopped doing it. But from then on I heard this whine from the driveline. I have only put a 1000 miles on it since and the whine is getting louder. The hubs disengage fine (I can spin the front shafts by hand when parked) so I think the problem may be in the front transfer case. I changed the fluid last week with Dextron IV ATF. The orig. fluid looked clean and was full, no metal chips on the magnet but I though it was worth a shot. Then I used the 4WD last night (freak early snow here in southern PA) and today I am getting the horrible grinding again but this time I could not get it to stop. Any thoughts, I am desperate and low on cash to pay a shop just to scratch their heads?