Hello, this is my first post though I am an avid visitor here. I have a 2009 Prius 203,000 km. About four weeks ago I noticed a low pitched grinding noise at about 30 - 50 km/h. This is especially present in the beginning of any drive. Occasionally it will turn into a helicopter like noise at 50 - 70 km/h. Seems to be coming from front, probably driver side. I thought it was a frozen caliber but mechanic said brakes are good. I changed tires ( winter tires), noise is still present. On jacks ive spun front tires with hand and nothing abnormal. I haven’t yet tried spinning with accelerator on jacks. Wheel bearings? A week or two before the noise appeared I was driving on the highway and the car seemed to slowly sway back and forth in the lane. A very slow sway. I had to slow down for the rest of the trip. But then this went away and never came back. Could it be related? Many thanks for the help.
welcome! also inspect the cv joint boots for tears, cracks, leaks. these things can be hard to diagnose, and may take time.
Well, the noise got worse so I’m taking it to mechanic tomorrow, I’m pretty certain it’s the wheel bearing.
so it was indeed a wheel bearing, front driver side. Oddly enough, I did go about 5000km from the time I first heard the noise to getting it replaced... very hardy pieces those bearings.