Well, I brought my 97 LC to the dealer to fix the humming sound from front passenger wheel and also swirly sterring while driving on highway. 1. Humming sound - Front wheel bearing was loose so replaced it. 2. Swirly driving - Sttering gear needed to be adjusted to firm up the steering. Much improved but now, I am noticing the humm from rear passenger side but when I take the foot off the accelerator pedal, it goes away. What could be causing this?