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**pjmoreland** · 05-27-2023, 01:47 AM

Here are some photos of an original factory Eaton posi unit and a new Eaton unit (19556-010). Both of these are series 4 size carriers for use with standard thickness 3.73 or 4.10 gears. If you want to go with 3.07 or 3.42 gears, then you will need a series 3 size carrier.

The posi carrier has the easy-to-spot springs and plates in the center of the carrier, whereas an open carrier will not. I'm not sure about the casting numbers for original units, but here is a new Eaton series 3 carrier:

https://www.summitracing.com/parts/etn-19587-010

Edit - It appears that the casting number for a factory series 3 posi carrier was 32212.

https://www.stevesnovasite.com/threa...ential.411706/

05-27-2023, 01:47 AM	#2
pjmoreland Senior Member Join Date: Jan 2005 Location: CA Posts: 5,349	Re: Verifying a Posi Differential unit? Here are some photos of an original factory Eaton posi unit and a new Eaton unit (19556-010). Both of these are series 4 size carriers for use with standard thickness 3.73 or 4.10 gears. If you want to go with 3.07 or 3.42 gears, then you will need a series 3 size carrier. The posi carrier has the easy-to-spot springs and plates in the center of the carrier, whereas an open carrier will not. I'm not sure about the casting numbers for original units, but here is a new Eaton series 3 carrier: https://www.summitracing.com/parts/etn-19587-010 Edit - It appears that the casting number for a factory series 3 posi carrier was 32212. https://www.stevesnovasite.com/threa...ential.411706/ Attached Images Last edited by pjmoreland; 05-27-2023 at 02:06 AM.