Originally Posted by WillC310
Does your 1200mi service record show no diff fluid change? I would check to see if it does, and if so, what fluid they used. Chances are they just used the diff fluid that doesn't have the booster in it that prevents the noise. Most dealerships don't carry/use the fluid with the booster in it for some lame reason.
Most dealerships don't carry the differential fluid with the FM boosters because it costs at least 3 times more than the standard cheap differential fluid.
As usual, it comes down to money.