Re: Pulsating noise from the front
Does the sound change when you turn in one direction vs. the other? If it is a wheel bearing, it should get louder when turning in one direction and quieter when turning in the opposite direction as the bearing is loaded an unloaded.
The noise you describe sounds more like a wheel bearing than differential.
You can also jack the front up and see if you can feel any play in the wheel bearing. If you grab the wheel at 3 and 9 and try to rock the wheel and then at 12 and 6 and do the same, if the bearing is really bad you'll feel movement. When lifting the car, follow all safety precautions before grabbing and shaking the wheels!