Hi Scotty,
My 2012 Mustang GT 6 speed develops a what sounds like a bearing noise starting at around 40-45mph (60-70 kph) that does not change if I take my foot off the gas pedal. The sound increases with speed and is not affected by either acceleration or deceleration. It is quite noticeable at highway speeds. I'm sure that it is not rear axle gear noise. I have not been able to determine the source of the noise - if it is caused by a a noisy rear axle bearing or a noisy front hub bearing assembly. I recently inspected both front hub bearings and noticed that there was a considerable build up oily dirt around the ABS tone rings and seal lips on both front hubs. It looks like grease has been leaking out of the hub bearing seals for some time. I had to use a small wire brush to clean this dirt accumulation from the ABS tone rings. Is it possible that one or both of the front hub bearings has lost enough grease as to cause them to be the source of the mysterious whining noise that I am experiencing, and should I replace both front hub bearings ? Thanks in advance.
If it’s indeed both front wheel bearings, sure, replace them both.
A quick way to check for a bad wheel bearing is to jack up the tyre & check for play at both the 12 & 6 o’clock positions, as well as 9 & 3 o’clock positions. If you feel play or hear a clunking noise, it’s the wheel bearing. Also you can try spinning the tyre by hand while holding the strut, and if the strut vibrates, it’s also a sign of a bad wheel bearing.
However, if you’re not sure of the source of the sound, here’s 1 technique -
