I was driving my 1984 240 DL on I-95 just north of Baltimore when I heard a high pitch, dull whining sound that would last for about a second and then come back every 4-5 seconds. Then, about 5 minutes later there was a real loud noise and the car sounded really rough, especially while my foot was off the gas. I got off a few exits early and drove home on normal streets in lower gears. The sounds wasn't quite as loud, but it was still way louder than it should have been. I checked under the hood and the oil levels seemed fine. Prior to the whining sound, the car was running/sounding fine. There didn't seem to be any loss of power after it started making this noise. When I tried to start it up this morning, it started making the exact same noises so I got I ride into work with someone else.

Any idea of what this might be? A friend said he thought it might be the AC belt or the power stiring belt. Thanks.

FYI: Its only got 117K miles.