Originally Posted by Rory McNeil
(Post 619396)
Jeff, was that weight difference with a limited slip diff, or a spool? Over 20 ears ago, when I switched my bracket car from an automatic to a Jerico 4 speed, I decided the old rearend needed updating. I had been using a Ford 9" with 33 spline Strange spool and axles, with a production Ford Nodular iron case, and an unbraced early style housing. After some research, I came to the conclusion that bracing the existing housing, buying an aftermarket case and bigger axles and spool would be comparable to scratch building a Dana 60. So I sold the old 9", and my buddy built a new Dana 60, using a thick tube (heavy) truck housing, billet caps, 35 spline spool & axles, and a T/A load bolt cover. Having heard all the stories about how heavy a Dana 60 was, I was pleasantly suprised when I weighed both rearends. Using the same model brakes, the Dana was a mere 6 pounds heavier than the 9". Now, keep in mind, the Dana had thicker, heavier axles, and was a thick tubed truck housing, while the 9" had a light, early housing and smaller 33 spline guts. I think the move to 35 spline axles in the 9", plus a braced housing would eliminate that 6 pounds. And if I bought an aftermarket iron case, be heavier. Now, I know an aluminum case would make the 9" that much lighter, but again, if I used a thin tube Dana housing, the Dana would also loose some weight. A Dana clutch style limited slip is a huge, heavy unit, replacing that with a spool drops a lot of weight. I can say, after 20+ years of 6000+ RPM clutch dumps, the Dana has been as reliable as an anvil. I have 3 sets of Pro gears of various ratios, and each set has at least 7 years on them, and they all still look great. Only strikes against a Dana that I see, is not as many ratios available as a Ford 9", but the 12 bolt is in a similar situation there as well. Plus the Dana is not as easy to change gears, as throwing another chunk in a 9", but again, same story with the 12 bolt. For my purpose the Dana is a great choice.
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