Volvo: 1992 Volvo 240, resonence, 1992 volvo 240

Question
The car has only 60,000 miles. There is an intermintante low pitched resonence that sounds like a 'howl'or 'moan'. First is was at speed of 50 mph+ now at street speeds. I have the car repaired at a dealership they said they fixed it. It came back.  

Answer
I'm going to need more information about where the sound is located.  Is it coming from the front or back, left or right side?  Can someone hear it from the outside (drive by them)?  Does it make it while you are accelerating or braking, or both?  Can you turn off the engine at speed and does the sound go away or remain?  Does it change with engine temperature, outside weather, etc?  This information is critical to tracking down a problem that, at this point, could be a ton of different things.  If you would like, get back to me with this info, and I'll do my best to help narrow down the issue.