I wonder what is causing this problem. Rear ends don't "just" leak. I can't believe it is a manufacturing problem. Design? Bad fitting parts from a supplier?

Did you ever see gear oil in the driveway, or residue beneath the differential housing? Or is this leak completely internal?

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Solstice GXP Coupe
You still don't need a trunk to haul ass...
even at Red Rock Canyon in Las Vegas!