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Broken 12 bolt?

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Old Sep 19, 2007 | 08:07 PM
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Default Broken 12 bolt?

I knew the diff in 12 bolts was weaker than others and was the weak link with a 6 speed car. The car is mostly street driven but will go 9's now that I got it to finally hook(apparently too good) last night and it blew the diff apart. It was a 33 spline moser.
How would a spool be on the street or is there a stonger unit available?I think it was an auburn
Attached Thumbnails Broken 12 bolt?-diff-003.jpg   Broken 12 bolt?-diff-001.jpg  

Last edited by 1BADAIR; Sep 19, 2007 at 09:06 PM.
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Old Sep 20, 2007 | 04:56 AM
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The weak link, the posi unit.
If your running 9s then put a spool in it. I run a spool in mine and its not as bad as I thought it would be. Its different than a posi of course but once you get used to it its no big deal. I run MT DRs and the soft tire tones down the spool.
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Old Sep 20, 2007 | 11:24 AM
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Looks like you broke the spider gears (and more). I broke a few teeth off the spider gears of an auburn once. Took the stock ones out of an open diff and put them right into the auburn. Thats when I realized the auburn isn't very strong if it's got the same sized stuff as stock.
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Old Sep 20, 2007 | 06:36 PM
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I agree with the post above, go with a spool in the 12 bolt. Bob
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Old Oct 17, 2007 | 02:10 PM
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it broke the spiders, pinion, twisted the spicer yoke on the trans and bent the ARP wheel studs on the left side.
installed a moser spool, pro street gears, mark williams billet trans yoke and new wheel studs and it seems to be holding now. Not to sure about street driving with the spool though
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