AW4 whining...... HELP!!

Hi all. I'm new here and have a question about my 96 AW4. A couple of days ago I noticed a whining noise coming from the front of the transmission/torque converter area. The noise is present in all drive ranges including reverse (goes away in Park and Neutral) and changes with fluctuations in RPM. I pulled the flywheel inspection plate and checked the flywheel to TC mounting bolts and all are tight. I'm thinking that either the torque convereter is starting to go or the transmission oil pump is the culprit. I should mention that I dropped the pan (the gasket was leaking) and replaced the filter and fluid (DEX3) the previous week. Is this a coincidence that this noise has suddenly come about? Has anyone ever had a similar problem on their AW4? Any help in diagnosis is appreciated. Thanks.

-RR

I have 4 XJ's and the older ones with more mileage whine when they are cold, but get quiet after they warm up. They usually last for a long time.