[John V.]

The '64 A Body axles were stamped with the numeric ratio on the RH (passenger) side axle tube for identification. Followed by an "L" if the Safe-T-Track option locking differential was included.

A 3.08 axle with open differential will be stamped:

"P 308"

A 2.56 axle with locking differential will be stamped:

"P 256L"

The prefix "P" meaning is not understood but likely means that Pontiac was the vendor/producer of the axle assembly.

After exchanging info with a guy who builds axle assemblies, I'm convinced what has been described as a "Buick" axle is bogus.

Champ, the stickers were not used until mid year (the actual timing of the label addition is in a Service Craftsman News or News Flash, I forget which) but the stamped codes were used all year.

The single letter code you posted only points to the ratio and brake type (std or metallic). The 2 or 3 identifies the differential type, open or locking respectively, but the letter alone was not used in any way for ID and was not the stamped code as you suggested.

The combination, such as 2D or 3K, was used for the labels but a letter alone would be pretty useless. And neither the letter alone or the 2 character code was stamped on the axle tube.

The paint color was used for ID early but for some reason, when Pontiac added the labels, they advised the paint daubs were no longer to be used for ID although I believe the paint daubs remained and the color decode was unchanged.

It is now obvious to me that the "converging rib" housing that OPH described earlier in the thread was NOT produced until perhaps '66 or later, not relevant to '64 or '65 for that matter.

And since the '64 Housing carries a PMD engineering p/n, I consider it a Pontiac part. The guy I spoke to claimed it was Buick produced, but Buick had their own p/n format, so his visual identification of the 9773369 Housing as a Buick part I consider incorrect.

Regardless, it is the common '64 GTO Housing, so to be correct, that is what you should expect to see under a '64 GTO.

It is interesting and informative that you found the one under a 06E Lemans. There was only a month left before the end of '64 production. If the '65 9779822 Housing was used under some late '64s as has been claimed by some hobbyists, it doesn't seem like it could have been very many, if they didn't appear until July. One example doesn't make for any conclusion, but always like to collect the data points. Thanks!

[John V.]

I should also add that I remain curious about the 9773722 Housing that dld had and later sold. Why did it exist, what was the application for it, how common/uncommon might it be?

dld, if you see this, do you recall what the stamp code was on it?

[remy30006]

my car is a 01E build date that came with 3:23 gears with safety track and the GTO rear end is out of a car with a date of 02A with 3:23 gears and no safety track would the only stamping number difference would be its missing an L after P323?

[dld]

Originally Posted by John V.

I should also add that I remain curious about the 9773722 Housing that dld had and later sold. Why did it exist, what was the application for it, how common/uncommon might it be?

dld, if you see this, do you recall what the stamp code was on it?

yea i got my ears on . the housing was out of a 64 tempest. got it at Carlisle years ago. seller had most if the car there. really did not have much other than parts from that car. it was a open rear 3.08 it had a series1 carrier. junk to me . so trashed guts. i did not take pic of id info.that housing did measure out to be the correct width and all mounting points were correct for a A body

if you remember the post on assembly date codes. i read where pont stamped the rear cover and buick stamped the under side of right tube. i don't remember how olds did it. just as a point.



ps ...could have been a 2.56 even more horrible. had a huge pinion gear

[John V.]

Originally Posted by remy30006

my car is a 01E build date that came with 3:23 gears with safety track and the GTO rear end is out of a car with a date of 02A with 3:23 gears and no safety track would the only stamping number difference would be its missing an L after P323?

Yes. "P 323 L" would indicate the locking differential inside.

[John V.]

Originally Posted by dld

yea i got my ears on . the housing was out of a 64 tempest. got it at Carlisle years ago. seller had most if the car there. really did not have much other than parts from that car. it was a open rear 3.08 it had a series1 carrier. junk to me . so trashed guts. i did not take pic of id info.that housing did measure out to be the correct width and all mounting points were correct for a A body

if you remember the post on assembly date codes. i read where pont stamped the rear cover and buick stamped the under side of right tube. i don't remember how olds did it. just as a point.



ps ...could have been a 2.56 even more horrible. had a huge pinion gear

I have another idea that I keep meaning to check out. I'll have to remember to check and report back.

But I was wondering if maybe yours was from a 3.90/metallic brake axle. Thought maybe it was a "HD" Housing for such a special application. Obviously that is a dead end.

I don't recall the post you mention. But I am fairly certain Pontiac assembled these rears themselves and supplied them to Buick & Olds for some applications. There is even some indication of that in the '65 Olds Assembly Guide. And AFAIK, the stamped code (numeric ratio code in '64 or 2 character manifest letter code in '65) was always on the RH axle tube on the back side, stamped at axle assembly (so presumably by PMD) regardless of the intended application ('65 manifest letter codes were Div. specific, '64 were same across Divs.).

'64/'65 Olds & Buick may have used other rears of their own production also, depending on application.

The only reason the Olds & Buick usage is of any interest to me is that it is possible to find a "correct" rear for a GTO in an Olds or Buick. But you will always find a PMD rear under a '64 Tempest, assuming it is still the original.

Usually with the 9773369 Housing or alternately the 9773722 based on your example.

[dld]

The situation i have problem with is at the anex plants that did mutable A-car builds. Would it not seem plausible that they were supplied buy any of the three (bop) mfgs.
My talking with Bill ( gm worker @ bal ) he said all the Buick and Pont rears were the same.Remember they did not build Olds after 64 and a 1/2.

it currently makes sence that Pontiac Mich. plant would use only Pont parts or Lansing would use Olds parts . But BF KAS BAL could use any one of the three. Yes?

What I meant about assembly date codes was where each housing was completed as to gear and axle brake ect. Pont marked cover with a letter stamp buick stamped the bottom side of right axle tube with there marks. My thinking is the housing were founded at several plants and assembled where ever?? the different assembly codes gave indication as to who was the assembly division.

[dld]

Another example could be . My frame in my 65 12c Bal. car has a Chevelle frame under it . Or what would assumed to be . Given the part number. That # is also used in Olds A cars.

[John V.]

Hmmm, I was not aware of an assembly date coding. I have a couple complete '64 Pontiac rears and a '65 Pontiac rear. I'll have to check the covers out one day.

Was it you that has the '65 Olds Assembly Guide?

It includes a page for '65 Olds A body Rear Axle Assemblies.

I assume '64 was same situation but the Olds A.G. is specific for '65 and quite illuminating.

Olds did not produce their own Rear Axle for their '65 A Body, according to the A.G.

Instead, they purchased what they needed from Pontiac or Buick.

For Lansing, they purchased the "Axle Sub Assembly" by either the Pontiac p/n or Buick p/n respectively.

Example, PMD p/n 9779795 got them a Pontiac produced sub assembly with 3.08 gears and open differential.

Buick p/n 1370717 got them a Buick produced sub assembly with 3.08 gears and open differential.

At Lansing, Olds received the sub assemblies and then built them up to a complete Rear Axle Assembly that could be installed at Final Assembly.

At the satellite Plants, Pontiac & Buick shipped the complete ready to install Rear Axle Assembly, per the specifications that Olds set, but including their own respective axle sub assemblies.

The axle sub assembly included the fabricated Differential Housing and Axle Tube Assembly (consisting of the cast center housing with the pressed in axle tubes), the internal Differential Case with the appropriate Ring & Pinion Gears, the bearings and caps, pinion seal, the differential cover and gasket.

For supply to the satellite Plants, all other parts were also provided in a complete rear axle assembly.

But at Lansing, Olds received the sub assembly and added:

Axle Shafts
Brake Assemblies and gaskets
Brake Drums
Outer bearing retainer gaskets
Axle Tube Vent Assembly
Rear Parking Brake Cable Assembly

The completed assembly was given an Olds p/n. Same p/n was used regardless if the sub assembly was a Pontiac or Buick, so that Olds p/n 386105 identified a complete ready to install 3.08 Rear Axle Assembly with standard brakes and open differential.

When the complete assembly was shipped to the Satellite Plants, it was identified by this Olds p/n and also labeled with the Olds Manifest code sticker. This 3.08 Olds rear was sticker code SC.

When Pontiac produced the sub assembly, the cast Housing was their own casting, p/n 9779822.

The only thing I don't know is whether Buick cast their own center Housing p/n in '65, their only alternative would have been to use the Pontiac casting, but that wouldn't make sense.

I believe they must have produced their own and that it carried a p/n such as 136xxxx or 137xxxx (the Buick p/n format at the time).

I have looked around but it doesn't seem that Buick or Olds guys are much for nos., so I can't determine what the '64 or '65 Buick cast center housing p/n may be.

The only Buick p/n cast housing I have been able to find is p/n 1375689 but it looks like Buick may have released that p/n for '66.

Pontiac's '66 A Body housing was p/n 9783393 and it was also used in '67, also for the Firebird, though the axle tubes changed in '67 (and the Firebird didn't need the ears for on-housing bushings).

If anybody has access to original '64 & '65 Skylarks, maybe we could learn the housing p/n assigned by Buick.

did, I hope I have made it clear. Even at the satellite Plants, in '65 Pontiac used a different rear axle assembly than Olds did, and I assume Buick was unique also.

They may have looked virtually identical, but a Tempest could get a Pontiac WE code 3.08 axle assembly while an Olds got the SC code 3.08 axle. If the SC was produced by Pontiac, it contained the same axle sub assembly as the WE and they both had a 9779822 cast Housing.

I would guess Pontiac also supplied Olds in '64 with axle sub assemblies (they were assigned different p/ns in '64, 3.08 with open diff was p/n 9773137) or complete axle assemblies to the Olds spec & Olds p/n just like in '65. Perhaps Buick was an Olds vendor in '64 also.

But the cast housing p/n should be a dead giveaway as to whether the Olds rear was Pontiac produced or Buick produced.

Only if Buick did NOT have their own cast housing p/n would it not be possible to distinguish between them.

For the '65 Frame, Olds had their own Frame p/n for the extended A body wagon. Not sure if they produced any of them or if they were produced for Olds by AO Smith and/or Parish Pressed Steel.

For all other '65 Olds A body models, Olds relied on Pontiac p/n frames with the one exception.

Pontiac p/n frames were produced in house by Pontiac or alternately to the Pontiac p/n and spec by AO Smith & Parish. Stamped codes on the Frame identify the actual vendor/fabricator.

In '64, Pontiac also listed Chevy p/n frames for the Tempest.

I assume this may have been done especially for convenience of the satellite Plants that built B-O-P and Chevelles though I am not completely certain that the Chevy p/n frames were actually used for the Chevelle or if they were Chevy produced strictly for B-O-P use.

But it makes sense that the Chevy controlled Balt Plant made use of a Chevy p/n frame for your build.

I assume your Frame is p/n 3864503. This Chevy p/n was the alternate to Pontiac p/n 9780502. Both p/ns listed as alternates by Olds in '65.

You are correct that these are examples of shared parts usage. Although in the case of the rear axle assemblies it is a little more complicated.

Every '65 Olds A body regardless of where built, got an Olds p/n rear axle assembly installed under it.

But that Olds p/n was an assembly that mainly consisted of a Pontiac produced sub assembly or a Buick produced sub assembly regardless of whether the car was produced at Lansing or a satellite Plant.

The '65 Pontiac A body always got a Pontiac produced rear axle assembly with a Pontiac assigned assembly p/n and manifest code label unique to Pontiac, wherever it was built. Only choice would have been a Buick produced rear to a Pontiac spec but I have never heard of a '64 or '65 Pontiac A body having other than a Pontiac p/n cast housing so I doubt they used Buick as a vendor in '64 or '65.

Buick A body is not as clear to me, but I would kinda guess they all got the Buick produced rear axle assembly wherever the car was built. Only choice would have been a Pontiac produced rear to a Buick spec. Since Buick was producing some rear axle sub assemblies and complete assemblies for Olds, I doubt they needed Pontiac as a vendor.

And I would guess the same was true for '64.

Going thru this, I learned a whole lot more about the '65 Olds rear axle assembly then I really needed to know.

But didn't learn anything significant about the Pontiac rear axle assembly which is disappointing.

If kinda baffles me why some in the hobby have identified the '64 & '65 Pontiac cast housings as Buick produced. They carry PMD engineering p/ns.

The guy that I contacted that seemed certain that they were Buick produced was not conversant with the p/ns, he went on appearance and believes Pontiac didn't cast their own housing until '66.

From a performance standpoint, the early housings may be weak and worthy of disrespect.

But for someone like me that is primarily interested in the correct p/ns aspect of the hobby, ignoring the '64 & '65 Pontiac p/ns makes no sense. Worse is to claim they were Buick produced.

[remy30006]

Would anybody have pictures of how the paint color id codes looked like and locations? Thank you guys the information here is incredible!

[remy30006]

Looking the rearend over that came out of the GTO, the only stamps I can find on the axle tube are a single letter which does line up with the PHS documentation that only has a single letter chart for axle id. I cant find any P 323 number what so ever is this right? Also laying two axles next to each other I notice neither of the housings have a brake line tab on the far passenger side, small detail but seems strange.

Thank you!

[Simpson]

Rear date code from a 65 442. C2, March 2nd. Stamped on cover. Pontiac style rears.



Another, E7



Buick 8.2 in a 65 442.



Buick 8.2 in very low mileage GTO. Taken from this site.



I have a Buick 8.2 taken from a 65 F85 in my barn. Small style 64 bushings, different brake springs.

Buick style,



Pontiac style,



Buick 8.2s, at least in 64-65 did not have any casting numbes on the center section. Bottom is smooth.

[Simpson]

Low mileage 64 GTO from Muscle Car Review, Buick rear end.

http://www.hotrod.com/muscle_car_rev.../photo_08.html

[dld]

Simpson

Those are the assembly date codes i speak of. these are the Pontiac marks .the buick assemblies were on bottom of rt tube AFAIK

casting numbers may be in different location all cast parts have a casting number.

[Simpson]

This rear center section has no code/number/stamping anywhere on it. Unless its on the inside, there is nothing to note what this rear end is.

[dld]

i certainly can't argue. your there. some time there on the area around the cover. you may check the width. from axle flange to flange 64 / 65 were 54 1/4. some argue 66 same as 65 ??? newer housings were about a inch wider.

[Simpson]

Original to a 65 Cutlass hardtop from New Mexico. Rear end is spotless, just surface dirt. If there was anything on it Id have found it. No axle tube code either.

[John V.]

First, I want to correct myself, the elimination of the paint daub was NOT the one on top of the Housing. At the beginning of the year, axle ID was by the stamped ratio on the axle tube and color marking on the end of the axle shaft.

Around January, '64, PMD announced by SCN, that due to manufacturing changes, the color coding on the end of the axle shaft could no longer be used for identifying the differential ratio. Only the stamped ratio on the axle tube could be used going forward.

This superseded the Shop Manual which showed that BOTH identifiers would identify the ratio.

The daub on top of the Housing I believe was used all year long, not sure what the decode was but basically about a 1" wide brush stroke on top of the Housing. I think if you do a search, pix of this paint daub have been posted here.

Simpson, for years I thought the '64 Pontiac Housing had no p/n on it. I was familiar with obvious cast p/n on the '65 unit, expected the '64 should have been marked the same way.

Turned out the '64 9773369 is in small characters and kinda obscurely marked right along a flange on the lower half.

Simpson, I mention this in case the Buick might be marked in a similar way.

Since Olds specified there own p/n brake assemblies, I'm assuming what you found coupled to the Buick axle assembly were Olds brake assemblies, not Buick. Not that I know what either the Olds or Buick looked like, but as I described earlier, the '65 F85 rear axle was made up of a Pontiac or Buick axle sub assembly but brake assemblies and other parts that went into the complete Olds rear axle assembly were Olds specified parts.

Good pix of the stamped codes on the covers, I will look closely on mine when I get time.

When you say Pontiac style '65 rears, do you mean they have the 9779822 Housings?

remy, except for what The Champ posted, I have never heard of a single letter code identifying the axle ratio for a '64 Pontiac axle.

I also have never seen one without the brake line tab, although I always thought they looked like they could easily come "unglued" if you pried them open.

Can you post pix of the letter code stamping? Since it came out of a 02A GTO and is a 9773369 Housing, something seems amiss for it not to have the numeric ratio stamp. Anything is possible but this just isn't the norm.

Have to say, a Buick rear in a '64 or '65 GTO still seems very unlikely to me. The low mileage doesn't sway me. Just seems pretty unlikely. Especially if the car was built at the Pontiac Plant (which I am not sure of).

Even if it is correct and original to this car, I rate it as very unusual and also not the norm.

[Simpson]

Originally Posted by John V.

First, I want to correct myself, the elimination of the paint daub was NOT the one on top of the Housing. At the beginning of the year, axle ID was by the stamped ratio on the axle tube and color marking on the end of the axle shaft.

Around January, '64, PMD announced by SCN, that due to manufacturing changes, the color coding on the end of the axle shaft could no longer be used for identifying the differential ratio. Only the stamped ratio on the axle tube could be used going forward.

This superseded the Shop Manual which showed that BOTH identifiers would identify the ratio.

The daub on top of the Housing I believe was used all year long, not sure what the decode was but basically about a 1" wide brush stroke on top of the Housing. I think if you do a search, pix of this paint daub have been posted here.

Simpson, for years I thought the '64 Pontiac Housing had no p/n on it. I was familiar with obvious cast p/n on the '65 unit, expected the '64 should have been marked the same way.

Turned out the '64 9773369 is in small characters and kinda obscurely marked right along a flange on the lower half.

Simpson, I mention this in case the Buick might be marked in a similar way.

Since Olds specified there own p/n brake assemblies, I'm assuming what you found coupled to the Buick axle assembly were Olds brake assemblies, not Buick. Not that I know what either the Olds or Buick looked like, but as I described earlier, the '65 F85 rear axle was made up of a Pontiac or Buick axle sub assembly but brake assemblies and other parts that went into the complete Olds rear axle assembly were Olds specified parts.

Good pix of the stamped codes on the covers, I will look closely on mine when I get time.

When you say Pontiac style '65 rears, do you mean they have the 9779822 Housings?

remy, except for what The Champ posted, I have never heard of a single letter code identifying the axle ratio for a '64 Pontiac axle.

I also have never seen one without the brake line tab, although I always thought they looked like they could easily come "unglued" if you pried them open.

Can you post pix of the letter code stamping? Since it came out of a 02A GTO and is a 9773369 Housing, something seems amiss for it not to have the numeric ratio stamp. Anything is possible but this just isn't the norm.

Have to say, a Buick rear in a '64 or '65 GTO still seems very unlikely to me. The low mileage doesn't sway me. Just seems pretty unlikely. Especially if the car was built at the Pontiac Plant (which I am not sure of).

Even if it is correct and original to this car, I rate it as very unusual and also not the norm.

Anything goes if the car came from a GMAD plant. I have a friend that has a 65 F85 with a Chevy 10 bolt, car built at Fremont.

Pontiac style rears, like this.

[dld]

off subject but POI

GMAD did not start until 1968. this was when GM took total control of Fisher. The assembly plants no longer were two separate entities. Although BOP or multi. lines of cars at same plant was started in the 30/40's.