Author Topic: Posi tag on rear before or after painting  (Read 9789 times)

Mike S

  • Hero Member
  • *****
  • Posts: 2665
    • View Profile
Posi tag on rear before or after painting
« on: December 29, 2017, 03:22:25 PM »
 Here's a splitting hairs question....
For posi differentials....was the red triangular 'Use Positraction Diff Lubrication....." tag on the fill plug when the assembly was painted black? Or was it installed afterwards.
I assume if it was on the fill plug prior to painted that it would be masked somehow. And did the original tag have a slit on the end to slip over the plug neck.

Just curious,
Mike
67 04B LOS SS/RS L35 Hardtop - Original w/UOIT
67 05B NOR SS/RS L35 Convertible - Restored

bertfam

  • Hero Member
  • *****
  • Posts: 4492
    • View Profile
Re: Posi tag on rear before or after painting
« Reply #1 on: December 29, 2017, 10:54:02 PM »
Mike, this would be a good question for John. I'll see if I can get him to reply.

In the meantime, here's what I believe.

The axle was painted at the axle assembly plant (i.e. the Detroit Gear and Axle plant), but not filled until it got to the vehicle assembly plant (Norwood or Van Nuys). This leads me to believe that some kind of plug or cover may have been used to cover the fill hole when the axle was painted, and then the plug and tag (which came as a "unit" - P/N 3866433 - see below) installed after the axle was filled.

Of course, this is just a guess on my part, but it seems to me that if the "unit" were painted at the axle plant, it would be difficult at best to completely mask off the tag and I don't recall ever seeing any overspray on any posi tags.

Ed

JohnZ

  • CRG Member
  • *****
  • Posts: 4365
    • View Profile
Re: Posi tag on rear before or after painting
« Reply #2 on: December 30, 2017, 12:12:48 AM »
Guys -

The axle left Detroit Gear & Axle with no lube, but with the 4-sided plug in the fill hole. On the Chassis Line at the car assembly plant, the plug was removed, the axle was filled (with Posi lube if it was a Posi, or with regular hypoid lube if it wasn't), and the plug was re-installed (with the red plastic Posi tag added if it was a Posi axle).  The "unit" shown was a Service part for the dealers.  :)
'69 Z/28
Fathom Green
CRG

Mike S

  • Hero Member
  • *****
  • Posts: 2665
    • View Profile
Re: Posi tag on rear before or after painting
« Reply #3 on: December 30, 2017, 04:42:43 AM »
 Thanks Ed and John. And welcome back, John!

Happy New Year....
Mike
67 04B LOS SS/RS L35 Hardtop - Original w/UOIT
67 05B NOR SS/RS L35 Convertible - Restored

bcmiller

  • CRG Member
  • *****
  • Posts: 4011
    • View Profile
Re: Posi tag on rear before or after painting
« Reply #4 on: December 30, 2017, 09:31:57 PM »
John also said
“Yes, the plug was present when the axle was painted at Gear & Axle. The Posi tag was installed by the axle fill operator at the car assembly plant.”

From what I have seen (Bryon) the paint that was used was cheap and didn’t stay on very long on most cars. And I don’t remember seeing any tags that were split. 



Bryon / 1968 Camaro SS 396 coupe - now old school 468 big block
1967 Camaro RS/SS 396 coupe L35/M40 - 4 generation family project
Looking for 68 Camaro with body # NOR 181016

ZLP955

  • Hero Member
  • *****
  • Posts: 2186
    • View Profile
Re: Posi tag on rear before or after painting
« Reply #5 on: December 30, 2017, 11:38:57 PM »
Did the assembly-line posi tags have 'DIFF.' or 'DIFF'?
Tim in Australia.
1969 04A Van Nuys Z/28. Cortez Silver, Dark Blue interior, VE3, Z21, Z23, D55/U17, D80, flat hood.
Sold at Clippinger Chevrolet in Covina, CA.
AHRA Formula Stock at Lions Dragstrip, NHRA E/MP at Pomona Raceway

68Zproject

  • Hero Member
  • *****
  • Posts: 1868
    • View Profile
Re: Posi tag on rear before or after painting
« Reply #6 on: December 30, 2017, 11:42:16 PM »
Yes, what did the assembly line tags look like?
68Z28

Mike S

  • Hero Member
  • *****
  • Posts: 2665
    • View Profile
Re: Posi tag on rear before or after painting
« Reply #7 on: December 30, 2017, 11:50:48 PM »
Did the assembly-line posi tags have 'DIFF.' or 'DIFF'?
  I asked this a few years back and it was DIFF.
http://www.camaros.org/forum/index.php?topic=10511.msg79784#msg79784

Mike
67 04B LOS SS/RS L35 Hardtop - Original w/UOIT
67 05B NOR SS/RS L35 Convertible - Restored

BillOhio

  • Hero Member
  • *****
  • Posts: 1179
    • View Profile
    • photobucket
Re: Posi tag on rear before or after painting
« Reply #8 on: December 31, 2017, 02:38:14 AM »
Mine has the period
1969 Z28, Burgandy, numbers matching, 12,900 miles
1968 RS 327 4 speed
1970 Z28 M22 4:10 bought from original owner
1961 Chrysler 300G convertible

Camarocards

  • Member
  • ***
  • Posts: 243
    • View Profile
Re: Posi tag on rear before or after painting
« Reply #9 on: December 31, 2017, 01:33:34 PM »
  I asked this a few years back and it was DIFF.

Mike,

Was it “DIFF.” for just ‘67 or was it that way for ‘68 and ‘69 as well?

Thanks,

Bob
Bob
'68 SS L35 01D

68camaroz28

  • Hero Member
  • *****
  • Posts: 2232
    • View Profile
Re: Posi tag on rear before or after painting
« Reply #10 on: December 31, 2017, 01:46:50 PM »
Our 68Z had the "Diff." with the period and if I remember correctly that is what the NCRS judging manual states.
Chick
68 Z/28 NOR 01B Orig motor/trans/rear
69 Z/28 NOR 07A Orig Block & GM Cross-ram/carbs
69 L34 Rest. Nova Father/Son Car
69 L78 Surv Nova Purch 4/69 31K miles
67 L89 Corv Tribute
68 Corv 427/400 Orig motor
07 Corv Z06
R 68Z build- http://www.camaros.net/forums/showthread.php?t=182584

Camarocards

  • Member
  • ***
  • Posts: 243
    • View Profile
Re: Posi tag on rear before or after painting
« Reply #11 on: December 31, 2017, 02:26:47 PM »
Hmmmmm....ALL of the Camaro vendors sell a ‘68 and up tag with a 3/4” hole that have “Diff” without the period. Paragon sells one with the period but the hole looks to be 1”.

https://www.paragoncorvette.com/p-359540-rear-differential-carrier-tag-posi-traction.aspx

Did the ‘68 and up tag use a 3/4” or 1” hole? Is this a case where the Camaro repro parts are yet again wrong?

Bob
Bob
'68 SS L35 01D

bertfam

  • Hero Member
  • *****
  • Posts: 4492
    • View Profile
Re: Posi tag on rear before or after painting
« Reply #12 on: December 31, 2017, 03:36:44 PM »
Yes, through late 1967 production the plug was 3/4 x 14 (Service P/N 3866433 - "Plug & Tag"), then starting late 1967 production (exact date unknown) and after, the plug was 1/2 x 14 (Service P/N 3931171 - "Plug & Tag").

Ed

Camarocards

  • Member
  • ***
  • Posts: 243
    • View Profile
Re: Posi tag on rear before or after painting
« Reply #13 on: December 31, 2017, 06:04:19 PM »
Thanks Ed.

So let me see if I understand this correctly....

1. All ‘67-‘69 tags should have the period after “DIFF” regardless of the diameter of the threaded portion of the plug.

2. The diameter being referred to by many of the repro suppliers is the diameter of the hole in the tag not the diameter of the threaded portion of the plug. For example HBC (http://www.heartbeatcitycamaro.com/store/category/11/212/Rear-Axle-Parts/)

3. The tag being sold by Paragon (https://www.paragoncorvette.com/p-359540-rear-differential-carrier-tag-posi-traction.aspx) has the period after “DIFF” but with the larger diameter tag hole which, for example, contradicts what the Camaro repro suppliers are advertising for the ‘68 and ‘69 tag. Did the Corvette use a different plug that would use the larger diameter tag hole? Will this tag work with the later 1/2” Camaro plug?

Sorry for the questions but I didn’t think a lousy period would cause me so much confusion.😁

Bob
Bob
'68 SS L35 01D

68camaroz28

  • Hero Member
  • *****
  • Posts: 2232
    • View Profile
Re: Posi tag on rear before or after painting
« Reply #14 on: December 31, 2017, 06:59:29 PM »
Original tag from our 67 Corvette has the period after DIFF.
Chick
68 Z/28 NOR 01B Orig motor/trans/rear
69 Z/28 NOR 07A Orig Block & GM Cross-ram/carbs
69 L34 Rest. Nova Father/Son Car
69 L78 Surv Nova Purch 4/69 31K miles
67 L89 Corv Tribute
68 Corv 427/400 Orig motor
07 Corv Z06
R 68Z build- http://www.camaros.net/forums/showthread.php?t=182584