So I noticed when I was driving on the highway tonight an odd sound....it sounded almost like a small dirt bike. When I accelerated it got higher and went down went a slowed down. I parked the car and revved the motor in Park and Neutral but no sounds. But when I started driving again it was making the same noises. Is this a tire issue, a hub issue or something else? I manually checked air pressure in tires and they were all at about 34-35psi. I did have to replace a front and rear wheel hib last year, could this be the other two? Any thoughts are appreciated.