I have a 2006 Lexus RX 330, performs well, but for the past year maybe, I have heard this low roaring sound that I thought was from the rear but now I’m feeling I hear it all around. As I slow down to a stop sign I do hear of wavering in the sound kind of like a Woo woo woo woo pattern. 
I just got it out of the shop for Val covers, and I asked the mechanic, he sees no leaks, and says it could be a wheel bearing, but I’m not sure what else he said I can’t remember. 
Could it just be the tires, they Still have some life in them, or could it be the wheels themselves? Or do you think it might be something else? According to the mechanic there are no other leaks in the back.

Thank yoStill have some life in them, or could it be the wheels themselves? Or do you think it might be something else? According to the mechanic there are no other leaks in the back.

Thank you so much,

kate {black}:idontknow: