That there you have is the Auburn cone style sure grip. Considered by the industry as the superior design for it's function, many people still prefer the Spicer Powerlok for it's "rebuildability". When 65barracudadude is referring to the earlier Dana unit, he is referencing the Spicer unit, as Spicer is a division of the Dana corp. The Auburn has been considered non-rebuildable, although there is a way to restore it to servicability. You simply mill off the bottom of the cone and replace the mill thickness with shims on the top to make up the difference. The one setback you may find is that if the cone was allowed to bottom out and score the housing, you will need to find another housing. Not the carrier case, the suregrip housing. I would inspect that rearend thoroughly due to the damage, but I would suspect that the damaged pinion gear has already been replaced. The suregrip unit itself can be removed from the unit and used in any carrier housing, so it doesn't matter if you have a 741, 742 or 489 case, the suregrip unit will fit them all. I am with the camp that gives the 741 it's due, it is not an inferior unit, just overlooked because of the availablilty of the larger pinion shaft sizes of the 42 and 489 case. Good luck with your project, Geof
