Tech Q & A In The Grip By Richard Ehrenberg Last updated Feb 14, 2023 0 Share I have a Sure Grip made in 1967. I took it apart andall looks good including theclutches. The two outboardclutch plates look to be concaveinstead of flat. Is this aflaw, or is it this way by design.Design. See drawing below. Exploded view of clutch-typeSure-Grip differential (Power-Lok), showing correct assembly. 4 1 vote Article Rating 0 Share FacebookTwitterGoogle+ReddItPinterestEmailLinkedin