I have a 2004 malibu and when I am around 45 and higher speeds and turns slightly to the left (and only to the left), it makes a growling noise. I have checked all of the wheels to see if something is possibly rubbing, and it isn't. It does seem to get worse as I increase the speed, however, I don't put her on the highway much as I am worried about a component going out while going 65-70 MPH.

 

Welcome to the forum. It's probably the passenger side wheel bearing. Bad bearings hum, whir, or roar (like driving on truck tires) and are sensitive to shifts in load (lane changes or turns). Also, the hub with the bad bearing will get hot.