O type posi options?

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Old December 17th, 2012, 04:39 PM
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O type posi options?

I have an open 3.08 O type rear end. I also have a 2.78 posi O type rear end. Can I make a 3.08 posi out of these two by switching either the gears or the posi unit.
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Old March 27th, 2013, 08:03 PM
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you can use the 2:78 posi carrier up to 3:23 gears as long as they are both type O. I would replace all the bearings and races.
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Old March 28th, 2013, 12:03 PM
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All references I have read indicate that the posi carrier for the 3.08 (casting 671) is not the same as for the 2.78 gears (casting 673).
Check with Jim (MONZAZ) or Brian Trick.
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Old March 28th, 2013, 01:45 PM
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You will need to use a ring gear spacer to use the #673 posi unit with the 3:08 gears.I have made them before,but don't have any stocked right now.
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Old March 28th, 2013, 05:55 PM
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Fyi

Originally Posted by buzzbomb
you can use the 2:78 posi carrier up to 3:23 gears as long as they are both type O. I would replace all the bearings and races.
No. This is wrong. The 2.78 carrier can be used with 2.56 gears but another carrier is needed for the 3.08 and 3.23 gears.
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Old April 24th, 2016, 04:41 PM
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Do you still have the posi carrier and/or 3.08 gears?
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Old April 24th, 2016, 05:50 PM
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new posi unit

I have NEW O type posi units Eaton type
or a few reconditioned 8.8 ford units machined to 'o' type olds rear a little cheaper.

As Brian stated we can make you a spacer plate custom to fit the 2.56-2.78 posi unit you have to the 3.08 3.23 carrier gears.

Jim
JD
PM if interested in anything
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