12 Bolt carrier ID.

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BigBlockMan
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12 Bolt carrier ID.

Postby BigBlockMan » Thu Nov 12, 2009 7:55 pm

I am pretty sure this is for a 65-70 Pontiac 10/12 but...
Casting number ED30153 (153 only on Ring side)
Other casting marks..."ARMA STEEL"
Ring stamped 41-15 GM 1 70CY (no pinion but 41-15 = 2.73)
12 7/16 Bolts (haven't check but I assume LH thread)
Spider gear (differential pinion whatever) pin .745" in diameter
Ring seems to be 8.875 in diameter...haven't removed this one but the 72 10/12 ring I have sits nicely on top of this one and looks very similar.
31 spline 1.3125 diameter bolt in axles (don't have them but no recess for C-clip in side gears)
Single spring posi unit (one on each side) pic below.
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1112091726.jpg

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monzaz
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Re: 12 Bolt carrier ID.

Postby monzaz » Fri Nov 13, 2009 9:32 pm

Yes it is the older style 65-70 it has the smaller pinion shaft (spider gear shaft) and the 2 spring preload system.

Jim I think I also have one of these 162 casting?? I will double check it. What is the ring gear flange height on this one? You say it was a 2.73 yes?

Hopefully we will compile what units from the late sixties to the early 70's are interchangeable. lol.

There are also casting numbers that are 17-1, 17-2, 17-3 (these are from the 70's) 4 spring system eaton units with 28 and 31 axle spline units

250, 248, 31 spline axle units

all are corporate 12 bolts with 10 bolt covers....

I will get a list to you on all the info I have as soon as it is in order. Jim
J D Race

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BigBlockMan
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Re: 12 Bolt carrier ID.

Postby BigBlockMan » Sat Nov 14, 2009 10:00 pm

The flange height was the same as the 72 10/12 I have at 1.980 from the end of the bearing hub...Looks to be identical to the 72 version as far as dimensions go...smaller spider shaft and larger/longer pin bolt.

Here is a bit of interesting info for ya..the guy O got this carrier from said he had it in a 8.5" case and got the gear pattern set coreectly...just couldn't get the axles he had to fit....ponder on that for a while.

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monzaz
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Re: 12 Bolt carrier ID.

Postby monzaz » Mon Nov 16, 2009 8:07 pm

AH..... No way... It is too big a diameter of gear to fit the case. The pinion will probably fit as it has all the same dimensions as a 8.5 pinion.

You migth be able to fit the 8.5 unit into the 12 bolt / 10 bolt housing. BUT you will need the carrier with the a36 carrier bearing.

Just have to get things here back in order to start tinkering again...lol. Jim
J D Race


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