Tranny & differential decoding help
Thread Starter
Burning Brakes
Joined: Jan 2005
Posts: 1,163
Likes: 1
From: Indiana
Tranny & differential decoding help
Been crawling under my roadster doing some cleaning, lubrication and general maintenance. Decided to get the codes off the tranny and differential and could use some help decoding the numbers. I think I got all the locations.
Transmission
Shifter Cover 3884685 (Driver Side)
Passenger Side
3886010
US Patent #3088336 GM
General Motors Corporation
Passenger Side (edge of case, vertical STAMP)
P01004
Just above and in front of the fill plug
4 (cast, large, like 1")
6 (cast, smal 1/4", with 3 dots below it)
Tail Housing
3857584GM
Differential
464910 (bottom of rear cover)
GM8 (top of rear cover)
CJ12 1363 (Bottom of case)
J 7 2 (on the passenger, rear side of the back of the case, very hard to read)
As usual. . . advise and suggestions are always appreciated!
ps. found my oil leaks are the valve covers!
Transmission
Shifter Cover 3884685 (Driver Side)
Passenger Side
3886010
US Patent #3088336 GM
General Motors Corporation
Passenger Side (edge of case, vertical STAMP)
P01004
Just above and in front of the fill plug
4 (cast, large, like 1")
6 (cast, smal 1/4", with 3 dots below it)
Tail Housing
3857584GM
Differential
464910 (bottom of rear cover)
GM8 (top of rear cover)
CJ12 1363 (Bottom of case)
J 7 2 (on the passenger, rear side of the back of the case, very hard to read)
As usual. . . advise and suggestions are always appreciated!
ps. found my oil leaks are the valve covers!
Last edited by Frankenvette 63; Dec 26, 2005 at 02:00 PM.
Team Owner
Joined: Oct 2000
Posts: 38,897
Likes: 1,926
From: Washington Michigan
Trans side cover was used in '66-'68, main case (3885010, not 6010) was used in '66-'67, tailhousing was used from '65-up, P0104 means the assembly date was January 4th, and the 6 with three dots means the main case was cast the third week of June (check the stamped "P" number again, as raw case castings didn't usually sit around for five months).
The CJ 12 13 63 stamping on the bottom of the diff is a 3.08 Posi assembled on December 13, 1963. Dunno what the 464910 is - the rear cover casting number is at the top, right against the bottom of the crossmember. Is the J 7 2 on the diff case, or on the rear cover?
The CJ 12 13 63 stamping on the bottom of the diff is a 3.08 Posi assembled on December 13, 1963. Dunno what the 464910 is - the rear cover casting number is at the top, right against the bottom of the crossmember. Is the J 7 2 on the diff case, or on the rear cover?
Thread Starter
Burning Brakes
Joined: Jan 2005
Posts: 1,163
Likes: 1
From: Indiana
Originally Posted by JohnZ
Trans side cover was used in '66-'68, main case (3885010, not 6010) was used in '66-'67, tailhousing was used from '65-up, P0104 means the assembly date was January 4th, and the 6 with three dots means the main case was cast the third week of June (check the stamped "P" number again, as raw case castings didn't usually sit around for five months).
The CJ 12 13 63 stamping on the bottom of the diff is a 3.08 Posi assembled on December 13, 1963. Dunno what the 464910 is - the rear cover casting number is at the top, right against the bottom of the crossmember. Is the J 7 2 on the diff case, or on the rear cover?
The CJ 12 13 63 stamping on the bottom of the diff is a 3.08 Posi assembled on December 13, 1963. Dunno what the 464910 is - the rear cover casting number is at the top, right against the bottom of the crossmember. Is the J 7 2 on the diff case, or on the rear cover?
As for the differential, the J 7 2(?) is cast into the right (passenger) side of the rear cover. As you look at the cover from behind, the casting is on the right edge of the case. I have confirmed the 3.08 ratio. As for the casting number location you describe, I cannot locate it.
John Z, this is a driver, probably doesn't much matter in the scheme of things. I really wanted to know for parts ID when and if required. Again, thank you for the assist!
ps. is there a book or manual that identifies all the mid-year components by casting, serial number and/or appearance?
Team Owner
Joined: Oct 2000
Posts: 38,897
Likes: 1,926
From: Washington Michigan
Originally Posted by jsdailey
ps. is there a book or manual that identifies all the mid-year components by casting, serial number and/or appearance?
