The part number for GM power steering fluid changed at some point from 1050017 to 89020661. Anybody know what has changed, if anything? The aftermarket fluids at the parts stores (Autozone, Advanced Auto Parts, O'Reilly) all reference the 1050017 part number and a GM Spec - GM9985010. Is there a new spec for 89020661? Is the new stuff the same color as the old stuff?