Hi.\nI have a 2001 Saturn SL1. 109k miles. 4 brand new tires (last\nweek). For the past 6months, something in front left of car makes a\n"grrrrr" noise which only starts to be noticeable when going faster\nthan 30mph, and increases in volume, and pitch, with speed. I don't\nthink it's the engine or transmission, because I was on highway and\nbumped into neutral and could rev the engine but the grrr sound was\nstill constant and only changes pitch with speed. Also changes pitch\nmomentarily if I hit a dip in the road. Even the 4 new tires I\ninstalled make no difference in the grrr. Wheels and stearing wheel\ndoesn't really shake or anything abnormal. I've read about wheel\nbearings potentially being such a cause. Or maybe, if pitch changes\nwhen I hit a dip, could it be an engine mount problem? Any ideas?\nThanks\nTheodore.