1976 Positraction Identification
Thread Starter
Racer
Joined: Jan 2007
Posts: 427
Likes: 1
1976 Positraction Identification
I am starting the rebuild of the differential. I need to know what 'posi' unit is in the housing. The clutch pack has 4 pressure plate springs and steel clutches.
Thanks
Dano,
Thanks
Dano,
Race Director
Joined: Oct 2000
Posts: 12,657
Likes: 3,117
From: Shamong, NJ
All 63-79 Corvettes used an Eaton posi unit. The 80-82 rear uses a Dana.
There are some differences to the units used in 63-64, compared to the later units. For 65-79, the posi components are all the same. The carriers for 4 series gears are a different diameter than 3 series carriers, to accommodate the larger ring gear, but they still use the same clutch packs.
Starting in 1970, positraction was made standard on the Corvette, prior to that, it was optional.
There are some differences to the units used in 63-64, compared to the later units. For 65-79, the posi components are all the same. The carriers for 4 series gears are a different diameter than 3 series carriers, to accommodate the larger ring gear, but they still use the same clutch packs.
Starting in 1970, positraction was made standard on the Corvette, prior to that, it was optional.
Thread Starter
Racer
Joined: Jan 2007
Posts: 427
Likes: 1
I have a unit that has 4 springs and from the GM part book identifies this as a GM unit in comparision to a Eaton unit having only 2 springs in the illustration. I am only going by the 'spring' count to identify the posi.
The clutches are metal and 'daisy' looking. I have ordered metal clutches.
From the feed back it appears 1976 is a Eaton unit, is this correct?
Dano,
The clutches are metal and 'daisy' looking. I have ordered metal clutches.
From the feed back it appears 1976 is a Eaton unit, is this correct?
Dano,
Thread Starter
Racer
Joined: Jan 2007
Posts: 427
Likes: 1
Futher to my last post I found a number on the carrier that is 32297 PM 1. In looking in the parts book under section 5.510 this number shows up as a Eaton case GM part number 3997926 which by the way showed stock when checked. It appears to be a Eaton, does anyone disagree?
I am seaching for the Pionion Shaft Lock screw, Eaton part # 93465, GM # 3869319. Can anyone tell me where I can find this screw for the differential side pinion shaft.
Dano,
I am seaching for the Pionion Shaft Lock screw, Eaton part # 93465, GM # 3869319. Can anyone tell me where I can find this screw for the differential side pinion shaft.
Dano,
Race Director
Joined: Nov 2006
Posts: 19,445
Likes: 353
From: Athens GA
St. Jude Donor '12-'13, '15- '16-'17-'18-'19, '21
Futher to my last post I found a number on the carrier that is 32297 PM 1. In looking in the parts book under section 5.510 this number shows up as a Eaton case GM part number 3997926 which by the way showed stock when checked. It appears to be a Eaton, does anyone disagree?
I am seaching for the Pionion Shaft Lock screw, Eaton part # 93465, GM # 3869319. Can anyone tell me where I can find this screw for the differential side pinion shaft.
Dano,
I am seaching for the Pionion Shaft Lock screw, Eaton part # 93465, GM # 3869319. Can anyone tell me where I can find this screw for the differential side pinion shaft.
Dano,
I also need 2 of these pins (screws) also but none of the usual suppliers carry them
It is thinner than many other GM pins like the Camaro.
Anyone got any ideas?????
Txs
Dennis
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