Search for my post from a year ago on the rear diff. Pre-2005 ones are at risk. Mine was the first reported here, now yours. Many reports from down under. You are looking at $200 for the revised parts to insure it doesn't happen again. If you wheel, I would do it...

Big Truck: 00, 3.5, Endeavor, 5-Spd drive line in hand!
Little Truck: 87, 2.6T I/C, MT, LSDs, Tonneau Top
Her Truck: 03, 3.8, 20th Anniv, 65k
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