Hi Scotty, I have a 2010 Prius with 132000 miles. Lately I've notice a droning noise that starts up at 40 mph. I can only hear it at 40 mph or higher. I've taken the car up to 45-50mph and then shifted into neutral to see if the noise was coming from the drivetrain. But even in neutral the noise was present? Do you know where the noise could be coming from and how much it might cost to fix? Thanks
Sounds like a wheel bearing. Try to determine if the noise is coming from the front or the rear. You may want to get someone else to drive as you sit in the front seat, then the back seat.
If you can isolate the noise, you could rotate the front tires to the rear, rear to front, to see if the noise follows the tires.
If it does, it's a tire. If it doesn't it's likely a wheel bearing
