Author Topic: Differential Plant Code  (Read 1912 times)

Offline TonyH

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Differential Plant Code
« on: March 30, 2020, 07:37:51 AM »
Sorry if this is posted elsewhere within the site but I'm not finding it if it is. 

I'm trying to find a source that lists the plant codes for the differential tags.  I have an early 1968 San Jose S-Code and the differential tag is pretty bad due to corrosion.  Plant Code appears to be 936.  Understand all of the other numbers but what would 936 mean?

v/r
Tony
Tony

Driven San Jose 2/23/68 8R02S1427XX
Lime Gold GT Fastback

Offline Coralsnake

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Re: Differential Plant Code
« Reply #1 on: March 30, 2020, 09:54:52 AM »
I dont think thats a “plant” code.

It is an internal code that can be found on the build sheet . It coordinates to the axle ratio.

What is your axle ratio?

Offline Bob Gaines

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Re: Differential Plant Code
« Reply #2 on: March 30, 2020, 03:09:09 PM »
I dont think thats a “plant” code.

It is an internal code that can be found on the build sheet . It coordinates to the axle ratio.

What is your axle ratio?
+1 .for sure.
Bob Gaines,Shelby enthusiast, Shelby collector , Shelby concours judge SAAC,MCA,Mid America Shelby

Offline J_Speegle

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Re: Differential Plant Code
« Reply #3 on: March 30, 2020, 04:36:55 PM »
Agree with the rest - Surprise :)

It identifies the complete assembled rear end and would match the number found on the cars original buildsheet. 




On the third member metal ID tag




And on a paper (much easier to see quickly on the line) tag wrapped around the rearend housing normally under a spring U bolt to help hold it in place for a few hours



Worker at a  sub station would get a copy of the buildsheet - pull the correct axle while someone else identified and pulled the correct rear springs. Once assembled as a sub assembly they would be placed on a feeder that would take it to the car assembly line where it would be placed on belt "belt"  where the unibody was lowered over it and the exhaust system.

This practice is shown in a number of threads in  the Assembly Line discussion area of the site or do a search using "body drop"
Jeff Speegle

Anything worth doing is worth doing concours ;)

Offline TonyH

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Re: Differential Plant Code
« Reply #4 on: March 30, 2020, 07:56:47 PM »
Axle ratio is 3.25:1.  I never had the build sheet for the car.  First line of the tag is WES-M and the second line is 3.25 8A0 936 (if I'm reading it right).  I have to admit that I'm not seeing how the 936 would coordinate to a 3.25 axle ratio.  Maybe just a tracking number?

v/r
Tony
Tony

Driven San Jose 2/23/68 8R02S1427XX
Lime Gold GT Fastback

Offline J_Speegle

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Re: Differential Plant Code
« Reply #5 on: March 30, 2020, 08:34:47 PM »
................  I have to admit that I'm not seeing how the 936 would coordinate to a 3.25 axle ratio.  Maybe just a tracking number?


Like the WES-M the 936 was just what Ford assigned to that particular combination. There are tons fo them if you check out the MPC

The buildsheet and tag are from 68 S code applications and the paper tag is an example from a 68 9 inch application 
Jeff Speegle

Anything worth doing is worth doing concours ;)

Offline TonyH

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Re: Differential Plant Code
« Reply #6 on: March 30, 2020, 09:32:23 PM »
Tracking...thanks Jeff.

v/r
Tony
Tony

Driven San Jose 2/23/68 8R02S1427XX
Lime Gold GT Fastback

Offline 67gta289

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Re: Differential Plant Code
« Reply #7 on: March 31, 2020, 07:37:40 AM »
Interesting that the MPC tag diagram lists the three digit number in the lower left hand corner as the "plant code".  This could be interpreted as "the code identifying where plant where the axle was built" or "an code used for quick identification of the rear axle at the assembly plant" or ...

Is there any information available in the Marti report?  If I recall Marti reproduces these tags, so might be able to validate the number.  I have not used those services so can't say for sure.

Since Jeff's example with an 8J date links the WES-M assy to identification number 936, and you have an 8A date...you might have been given the answer.  Something closer to confirm that there was no change in between would be nice.

Jeff, it is my understanding that the axles were shipped out of the Sterling (Heights, Michigan) axle plant as complete assemblies, so would think that the tag was stamped and affixed at the axle plant.  That would mean that a 936 would be the same across all assembly plants.  Any comment or correction to this?
John
67 289 GTA Dec 20 1966 San Jose
7R02C156xxx
MCA 74660

Offline TonyH

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Re: Differential Plant Code
« Reply #8 on: March 31, 2020, 07:57:40 AM »
I'm working with Marti to get a replacement tag.  The original is totally corroded so trying to decipher the numbers.  After a couple days in Evapo-Rust, I can really only read the back of the tag.  I believe the second line is actually 3.25 8AD 936 versus 3.25 8A0 936.


v/r
Tony
« Last Edit: March 31, 2020, 08:00:27 AM by TonyH »
Tony

Driven San Jose 2/23/68 8R02S1427XX
Lime Gold GT Fastback

Offline 67gta289

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Re: Differential Plant Code
« Reply #9 on: March 31, 2020, 09:20:09 AM »
OK it sounds like you should be all set.
John
67 289 GTA Dec 20 1966 San Jose
7R02C156xxx
MCA 74660

Offline Coralsnake

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Re: Differential Plant Code
« Reply #10 on: March 31, 2020, 09:27:41 AM »
On the bottom of this page you can see a chart of 1968 Shelby rear axle codes. That three digit number always coordinates with the axle ratio

http://www.thecoralsnake.com/SUSPENSION.HTML

Offline 67gta289

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Re: Differential Plant Code
« Reply #11 on: March 31, 2020, 10:38:29 AM »
On the bottom of this page you can see a chart of 1968 Shelby rear axle codes. That three digit number always coordinates with the axle ratio

http://www.thecoralsnake.com/SUSPENSION.HTML

Based on the discussion above, I would agree that the three digit number always coordinates with the axle ratio.  But I would expand that to say that the three digit code always coordinates with ALL aspects of the rear axle, including but not limited to:

1. Axle ratio
2. open vs. locking
3. bearing sizes
4. flange to flange length
5. attachments for mounting in vehicle
6. spline count
etc.

At the Sterling axle plant, they would of course build a 9" 3.25 axle for a Mustang, but also for a Galaxie or Pickup Truck.  That is why they needed hundreds of three digit codes, not 10-ish
John
67 289 GTA Dec 20 1966 San Jose
7R02C156xxx
MCA 74660

Offline TonyH

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Re: Differential Plant Code
« Reply #12 on: March 31, 2020, 11:18:15 AM »
On the bottom of this page you can see a chart of 1968 Shelby rear axle codes. That three digit number always coordinates with the axle ratio

http://www.thecoralsnake.com/SUSPENSION.HTML

Thanks, was not tracking on this website.  Allot of good info.

v/r
Tony
Tony

Driven San Jose 2/23/68 8R02S1427XX
Lime Gold GT Fastback

Offline Coralsnake

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Re: Differential Plant Code
« Reply #13 on: March 31, 2020, 12:41:00 PM »
Yes thats Shelby only, designed to show a smaller sub-set

Offline RoyceP

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Re: Differential Plant Code
« Reply #14 on: March 31, 2020, 04:01:20 PM »
Bear in mind that the codes shown on that page are known to have been used on Shelbys but they are not Shelby only. They were used on other Mustang / Cougars as well in 1968.


Yes thats Shelby only, designed to show a smaller sub-set
1968 W code 427 Cougar XR-7 GTE Feb 23 Dearborn C6 / 3.50 open
1968 R code 428CJ Cougar XR-7 May 13 Dearborn C6 / 3.91 T - Lock