Chevy Nova Forum banner

1 - 7 of 7 Posts

·
Registered
Joined
·
879 Posts
Discussion Starter #1
Does anyone know anyother Axle decoding sites other then:

http://www.novaresource.org/axle.htm

I am selling my 12 bolt on Ebay right now:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=8051389441&rd=1&sspagename=STRK%3AMESE%3AIT&rd=1

My question is this:

I have had some specific questions from bidders who are very interested in this very rare 12 bolt out of a 66 Nova. I have decoded most of the codes however I am looking for additional info.

Here is what I have decoded so far:
FL0525E

Breakdown:
FL 3.55 posi 12-bolt
05 May
25 25th
E Eaton Positraction Differential

Now for the info I am unsure of.....and these are codes off of the center section that as of yet I have been unable to locate info on:

1. D57
2. GM9
3. NF3894860

Any help on decoding these would be awesome!

I am also looking for links to the sites that provide this info as well as some info on codes for the gearing inside, or at least the posi casting number info.

Thanks again all...as usual you always come through and I always appreciate the great info you have provided me with!

-John (forever grateful!)



1.
 

·
Premium Member
Joined
·
2,245 Posts
12 Bolt codes..

The #3894860NF is the Center Section Casting Number for a 1966-67 12 bolt in a Chevy 2...the D57 is the casting date; April 5th, 1967..the GM9 is probably some kind of corp casting stamp ID...Don't think it matters much as far as you are concerned. Dates and casting # seem to fit right into your axle assembly date stamp. Looks good....if gearing and posi unit are original then the casting number on the posi unit should be 30140PM1 and the stamp on the pinion gear would be 11-39 for 3.55. you should also see a date stamp on the ring gear. The FL axle code indicates that the car came with the large ring gear. hope this helps.

wilma:shh:
 

·
Registered
Joined
·
879 Posts
Discussion Starter #3
WILMASBOYL78 said:
The #3894860NF is the Center Section Casting Number for a 1966-67 12 bolt in a Chevy 2...the D57 is the casting date; April 5th, 1967..the GM9 is probably some kind of corp casting stamp ID...Don't think it matters much as far as you are concerned. Dates and casting # seem to fit right into your axle assembly date stamp. Looks good....if gearing and posi unit are original then the casting number on the posi unit should be 30140PM1 and the stamp on the pinion gear would be 11-39 for 3.55. you should also see a date stamp on the ring gear. The FL axle code indicates that the car came with the large ring gear. hope this helps.

wilma:shh:

Thanks Wilma! I have some people asking and one guy thinks it came in a 67 Camaro. Is that possible?

-John
 

·
Premium Member
Joined
·
2,245 Posts
67 rear axle..

The 67 Camaro and Nova axle housings are very similar in appearance. There is a slight difference in the spring perch mounting plate installation.and the Camaro had a kind of traction bar added on for V-8 applications. But the real evidence is the axle tube code..yours is unique to the Nova. Get a copy of Colvin's book Chevy by the Numbers and check out the section on the rear axles. All the info is there. Good luck.

wilma
 

·
Registered
Joined
·
879 Posts
Discussion Starter #5
WILMASBOYL78 said:
The 67 Camaro and Nova axle housings are very similar in appearance. There is a slight difference in the spring perch mounting plate installation.and the Camaro had a kind of traction bar added on for V-8 applications. But the real evidence is the axle tube code..yours is unique to the Nova. Get a copy of Colvin's book Chevy by the Numbers and check out the section on the rear axles. All the info is there. Good luck.

wilma
Thanks again. I did find another site for Camaro differentials...very interesting stuff!

http://www.chevy-camaro.com/parts/chevy-camaro-part-codes-diff.htm
 
1 - 7 of 7 Posts
Top