2001 Saturn Vibration from 40mph - 70mph

I've been getting a vibration in my car starting at speeds of approx. 40mph and progressively getting louder until about 70mph where it levels off.

Decelerating I notice the vibrations until I get below the 40mph where it clears up abit. When I shift to neutral it persists through that as well.

I have also noticed that when I make a slight turn to the right, such as on a bend in the freeway, the vibration disappears completely. Once I straighten out it returns.

I've had my tires balanced in an attempt to correct this without any change. Any help would be greatly appreciated.

Thanks!