I have a 2001 jeep grand Cherokee Laredo 2wd 4.0l inline 6. Stock. I have been hearing a grinding sound when In gear. When I drive and take off it's fine but once I ease off the gas is starts whining, and gets higher as my speed increases but no changes when I shift gears. When I come to a stop it winds down louder and almost has an underwater groaning sound. Now when I shift to neutral the sound stops when I step on the gas the sound goes away. When I turn my overdrive off the sound goes away. I've changed wheel bearings, roters and calipers, break lines. And I am at a loss. The jeep started stalling and now wont turn over but I think that may be a separate issue. Please help I'm throwing so much money at issues that aren't even the problem.

 

Also the sound seems to be from the front end which is why I thought it was wheel bearings. I had a guy put it in the air and in drive and he said it sounded like it was from the front of the transmission but after taking his advice on the calipers and roters I'm not sure I trust him.