CRG Discussion Forum

Camaro Research Group Discussion => Decoding/Numbers => Topic started by: dans67camaro on October 16, 2006, 12:23:55 AM

Title: 67 Camaro Series 3 Differential
Post by: dans67camaro on October 16, 2006, 12:23:55 AM: What is the correct series 3 casting number for a 67 - 12 bolt? I understand they can be either a Dana or Eaton unit. References have shown number 30140PM1 for a series 3, 3.08 to 3.73:1. I have located a unit with EDB30140 numbers. Which is correct? Thanks
Title: Re: 67 Camaro Series 3 Differential
Post by: hotrod68 on October 20, 2006, 04:09:44 AM: I've never heard of a Dana under a '67 Camaro from the factory! Dana 60s were way different from the 12-bolt and were original in the (gaaacckkkk) Chryslers. I'm no numbers guru but I guess it's possible a Dana carrier could be in a 12-bolt if that's what you're asking. But the 3-Series carriers were different between a 3.08 and a 3.73. If memory serves me correctly, 3.73 and lower ring gears on a 3.08 carrier required a spacer plate because the pinion gear was so much smaller. I believe the thicker carriers that didn't need spacers started with 3.55s. But again, I know next to nothing about the casting numbers and am relying on memory. Hope this helps and good luck!
Title: Re: 67 Camaro Series 3 Differential
Post by: dans67camaro on October 25, 2006, 05:40:46 PM: According to my reference material, the series 3 carrier accomodates a 3.08 to 3.73 R&P. Series 2 accomodates 2.73:1 and down. Series 4 accomodates 3.90:1 and up. I have an EDB30140 pn, but there is no manufacturer casting logo. After the pn there is a "PM w/ a circle around it" cast in (raised) followed by the number "1". Could it be a corporate (ie GM produced)?
Title: Re: 67 Camaro Series 3 Differential
Post by: JohnZ on October 26, 2006, 01:51:43 PM: Chevrolet didn't manufacture Posi units - they purchased them; the "EBD" indicates that it's from Eaton, which was Chevrolet's sole source for Posi.
Title: Re: 67 Camaro Series 3 Differential
Post by: hotrod68 on October 30, 2006, 05:14:16 AM: Thanks, dan--I remember now; A spacer was needed to go from a 3.73 to a 4.11 or lower gear until the aftermarket came out with the thicker ring gears. Zoom sold a lot of the spacer plates in the late '60s and early '70s! lol On the street factory Eaton 4-Series carriers were pretty rare, and everybody was running 4.11s or 4.56s--some hardcore guys even ran 4.88s and 5.13s. I ran 4.88s in my '64 Impala for awhile, but back then gas was only 32 cents a gallon. Oh, those were the days!
Title: Re: 67 Camaro Series 3 Differential
Post by: wonderdog on October 30, 2006, 05:12:40 PM: Am curious if your EDB30140 is the old, original Eaton built posi. Does it have the thick aluminum spring plates located UNDER the side gears??? Eaton aftermarket posi's have steel spring plates between the side gears.
Title: Re: 67 Camaro Series 3 Differential
Post by: dans67camaro on November 05, 2006, 01:44:29 PM: My unit does have steel plates between the side gears and springs. However, I believe it to be an original unit. How can I be sure?