Earliest 3969341 and Latest 3894860 axles

[ko-lek-tor]

Just drug this out of a barn in Indiana this afternoon. The "C" has been peened over, guessing at the factory. This axle has never had the numbers area cleaned off till I bought it. Will get a better pic of Cast Date tomorrow. Looks like F119 (June 11th)?

Do the guts match the code?  What are the dates of the ring and pinion?

Sorry, no guts. Just a housing, backing plates and cover. There were 3 more 1st gen 12 bolt housings in the back of the barn, 1 NOS! a fiberglass 69 front "doghouse" out back and several sets of BB heads and headers of unknown engine type inside. It was dark and cob webs everywhere. I came out with the housing , set of 026 square port heads and a pair of 69 Camaro buckets and of course, my rust free trunk lid. Next stop yielded a Victor 2-R tunnel ram, 2 660 holleys a 4346 holley, a oval port strip dominator and a bunch of other stuff...I'm broke! A lot of fun treasure hunting though.

[KurtS]

I went through my axle pics. There are several CBU axles with the C wiped out. Several are also untouched. I don't see the C removed on any other ratio.
I won't even hypothesize on this one......

[bcmiller]

Another piece of data.

860 housing
Casting date D28 9
BE0708G1

[bcmiller]

Updated January 11, 2021

Remember when submitting data - put all of the information requested in ONE POST - PLEASE.

Some notations have been made for C BU axles where the C has been peened. I did not note this on all of the ones listed.

Here is what we have so far.  We need more data points for axle assembly dates between early June and early August.  My apologies if your data was inadvertently missed.

It appears that the 341 casting number started being used in June. It appears that the 3 letter code had started by early August, possibly earlier. 

Remember that there was a shutdown for the latter part of July and into very early August. 

01C
BM 0124G1
860, casting date A 21 9

06A - 9N665238
BM 0625G
860, casting date unknown

07A - 9N6687XX
BU 0630G2
860, casting date E 26 9

Unknown build date
BE 0708G1
860, casting date D 28 9

08E  9N677954
C BS 0805G
341, casting date G 25 9

08C
C BL 0806G1
341, casting date G 23 9

Unknown build week and/or VIN
C BM 0807G1
860, casting date F 24 9

Unknown
No assembly stamp, possible warranty axle
341, casting date F 28 9

08D  9N6745xx
C BU 0818G2
unknown casting number or date

08D
C BS 0820G2
341, casting date H 11 9

08E, 9N677163
C BL 0812G2
341, casting date H 5 9

08E
C BU 0828G2
341, casting date H 13 9

08E
C BU 0828G2
341, unknown casting date

09A - 9N680789
C BU 0828   
341, unknown casting date

09A
C BU 0826 or 0828
unknown casting number or date

09C
C BU 0829G1
341, casting date G 31 9

Unknown build week and/or VIN
C BS 0829G1
341, casting date H 17 9

09C 9N684457
C BU 0829G1
341, unknown

09C   9N685397
C BU 0910G1
341, casting date I 2 9

Unknown build week and/or VIN
C BU 0916        C area is peened
341, casting date I 6 9

Unknown build week and/or VIN
C BU 0922G2    C area is peened
341, casting date I 11 9

10A
C BU 0929G1    C area is peened.
341,

Unknown build week and/or VIN
C BS 1028G1
341, casting date J 3 9

Unknown build week and/or VIN
C BE 1030G1 not peened
341, casting date J 3 9 or J 8 9 (hard to read)

[Kelley W King]

Bryon, I don,t think I gave you my 08E. I will try and get it to you in a day or so.

[ko-lek-tor]

... The "C" has been peened over, guessing at the factory...

I went through my axle pics. There are several CBU axles with the C wiped out. Several are also untouched. I don't see the C removed on any other ratio.
I won't even hypothesize on this one......

Rereading my own post I felt I was vague in saying, “done at the factory.”. The point I was trying to convey is that I have only known Camaro housings that had the “C” peened. I am under the belief that it was done at Norwood Assembly , as a Supervisor directive, and not done on axles dated the same at, say, the Nova Assembly line. I have been under the opinion that this peened “C” is a confirmation that the housing came out of a Camaro. Not to hijack this thread’s original topic, but it would be interesting to research this aspect of these C-less housings in the future. Further, Kurt’s observance of only the BU housings being affected, which I had not heard previously, is intriguing data to research, as well.

[bcmiller]

Back then this was not common knowledge to average gear head.  But if you were into racing and wanted to know what ratio you were getting - this was how it was done.

Obviously I have no way of proving what I think, but the evidence does support my thinking.  See my previous post as to why.

[69Z28-RS]

I still disagree with Byron re various/sundry owners 'peening' out the C in much the same way all across the country.. Unless it was some kind of 'Let's Obliterate the C'  underground conspiracy!      BUT...  you say you have HUNDREDS of examples - maybe if you compile the DATES, CODES, etc .. along with peened or not peened (or photos?), then I might come to agree with you, but in lieu of that....   I cannot believe such an 'aligned' conspiracy existed!

When I first examined my rear, I didn't even notice the 'C' (it was well in front of the 'code' and was not clearly stamped).   I think it was Kurt who suggested it looked like the C was there but damaged (perhaps by a stone or ?); now I would say it appeared like a single 'peen'!   But when we see MANY peened the exact same way, and all of them are in that 'transition period', where they are installing 1970 stamped rears in 1969 cars, I tend to lean towards the factory doing it (to appear more like the thousands of '69s assembled earlier in the year)...

Can you show us your database of '69 transition-period rears to help convince us of your theory?

[bcmiller]

You are saying they are all peened exactly the same way? Let’s see YOUR database that shows it.   

They are not all peened the same way. 

The axle plant just stamped what they were told to do. The vehicle assembly plant people would not have cared. The stamped code is NOT what was used on the assembly line for quick identification.
Typically quick ID was done by a sticker with the axle code on it - stuck on the outside of the brake drum. 

Here is a a link to a reproduction example from HBC.

http://www.heartbeatcitycamaro.com/store/product/24582/1969-Camaro-12-Bolt-COPO-BE-Rear-Axle-ID-Stickers-Pair/

You can disagree with me a thousand times, but it will be as productive as hitting your forehead against the wall.  Show me REAL PROOF otherwise and I will listen.   

[Kelley W King]

Not that I know, but just a thought. Think someone was thinking here are actually 70 model parts slated for 69 cars? Of course if only one ratio kind of makes that ? But I don,t think rocks or whatever did it. Could someone say" this load is going to Norwood and should not have the C" ? Maybe one guy on one shift who was later corrected. Maybe his work station was in the 12 bolt area? Lot of maybes here. I worked on an assembly line in the 70,s for IBM and heard phrases like that part came off 3rd shift because someone installed something differently. Not wrong just different.

[69Z28-RS]

1970 model Novas are the ONLY 1970 model car that used a rear end that was identical (in dimension, etc) to our '69 Camaros.   The 1970 Nova differentials, was produced in the same plant (EATON? - that produced Camaro differentials I believe).  Of course the 1970 Camaro had a different physical configuration (wider), but the 70 Nova differential was the same as the earlier '69 Camaro differential.  I just checked the 1970 Nova differential listing from Nova resource and it shows the leading 'C' in the code as we believe all '70 models had, BUT...  there was no 3.73 (BU) code used on 1970 Novas!  THIS fact would make the 'transition period' (Aug-Nov'69) 1969 Camaro 3.73 (BU) differentials unique coming out of the EATON plant at that time, as they were destined for extended 1969 Camaro production~   Maybe THAT precipitated the BU axles (for Camaros) to get 're-marked' by peening the 'C' off...??

1970 Nova differential codes

CBA - 2.56 open 10-bolt
CBB - 2.56 posi 10-bolt
CBC - 3.36 open 10-bolt
CBD - 3.36 posi 10-bolt
CBL - 3.07 open 12-bolt
CBM - 3.31 open 12-bolt
CBN - 3.55 open
CBP - 2.73 open 10-bolt
CBR - 3.07 posi 12-bolt
CBS - 3.31 posi 12-bolt
CBT - 3.55 posi
CBW - 4.10 posi 12-bolt
CPA - 3.08 open 10-bolt
CPE - 3.08 posi 10-bolt
CPI - 2.56 open 10-bolt
CPJ - 2.56 posi 10-bolt
CPO - 3.08 open 10-bolt
CPR - 3.08 posi 10-bolt
CPX - 2.73 posi 10-bolt

[bcmiller]

One big problem with that thinking Gary. There are documented original cars that do not have the C peened out.

[bcmiller]

The axles were assembled at Detroit Gear and Axle. I have tried for years to find a contact, just like I have tried to find a contact for Fisher Body at Norwood. No luck so far.
Eaton made the posi units, they did not assemble axles.

[bcmiller]

The peening topic was started in a new thread. If anyone want to discuss that, then please post anything related to that in that thread. Thank you!
http://www.camaros.org/forum/index.php?topic=16781.0

[bcmiller]

I went back and cleaned up / removed several posts not directly tied to the current topic.  This includes removing some of my own posts. 

Thanks for your help and cooperation in this thread.  I do appreciate it.