If that makes the whining noise stop — or sound significantly different — then the gears in one of your differentials could be worn out, or a differential may have run out of oil.

The front tires should spin opposite each other with very little resistance, just like an open differential. If they don’t, lower the vehicle and drive it around until the binding noise goes away.

If that makes the whining noise stop — or sound significantly different — then the gears in one of your differentials could be worn out, or a differential may have run out of oil.