I know even now, the clutch type is all Mopar offers for it. Auburn does show a cone type. Also another reason why it may spin both one minute and one the next is because to my knowledge, the 8.25 sure grip never had a spring preload pack in the center. It's a torque sensitive limited slip. When power is applied, the clutches "ramp" up against each other, real similar to the cone style, but with clutches and no preload springs. That could also be why it fails the spin test in park possibly. I too have seen an open differential spin both tires before......but not as positively as in his pics. First time for everything I guess. That's why I like this hobby. You see something new everyday.