We just purchased a used subaru forester with 109,000 miles on it. Passed inspection and seemed to be in good shape. We recently drove from PA to CT and back and the last hundred miles or so a very loud whirring noise started coming from the back of the car. We’ve driven it since then and the whirring noise is still there. Gets louder the more you accelerate. At high speeds it sounds like we are in a jet engine airline. And the whirring has a pattern to it, almost like we are driving over grating. Any ideas what this could be?
One guess is a rear wheel bearing.
Have someone check the fluid in the rear differential and the rear wheel bearings.
Very loud whirring noises are not good.
Are all four tires on this vehicle the same? Same make, same model, same tread wear?