K, I'll looking to get a posi unit (and possibly upgrade my 3.42's to 3.73's) and would like to do it economically as possible. I've found a couple different possibilites on Ebay, and want some opinions.

Used but in good shape Auburn unit for $200, and he said he'd give me a set of factory 3.73 gears for $75


Or and Eaton unit and 3.73 gears for the same $275 (that's a buy it now price, but saw in the past he sold the same unit for $233 so know can go for less.

My problem is this, the guy with the Eaton claims that they were taken from a factory sealed rear. Did GM put Eaton posi's in rears in the factory? If so what is their quality. I wanna make sure I don't get one of thos lousy s-10 units that''ll break rather quickly.

Thanks in advance for any help

 

I found a set of 373 in a junk yard about 4 years ago in a Firebird i think it was a 85 cant remember but no posi just gears and got a new Aburn and never hade any problems with the the gears or posi.