Body Number vs VIN Sequence Question.

[Eric DeVirgilis CLC# 8621]

I've noticed body numbers used by Cadillac are often out of sync with final build sequence as indicated by the VIN. Can anybody answer why this is the case? Did they just stockpile a bunch of bodies and pull them off the shelf in no particular order as needed before final assembly?

Also, what exactly was the difference between, for instance, an unfinished Series 62 body shell and the DeVille version before any differentiating body trim was added? Did they already have the holes drilled for the specific Series in question? Other than that, I have no idea how anyone would be able to tell which was which. 

[Ralph Messina CLC 4937]

Eric,

I hope I understood your question correctly.

I’ve never worked at GM but I have manufacturing experience with products having discrete serial numbers. When a production order is entered the trace-ability numbers of the components are established by manufacturing sequence of the individual components. The chassis sequence number, and engine number which are the same beginning with “0000001”, are assigned in sequence. The prefix to the sequence number identifies the year and model or series of that chassis.  In the case of the Eldorado engine there’s a prefix of “Q” to the engine sequence number. The body number is specific to a particular model, that is 6237, 6239, 6267SDX etc. If in a particular year the first 100 cars built were all CDV’s the chassis numbers and body numbers would be sequential from “1” to “100”. If the 101st car built was a 60 Special, it’s chassis would end in “101” but the body would be “1”.
The final assembly line is fed by multiple sub assembly lines all sequenced so that correct parts arrive at the correct station.  I’m certain there was some body inventory in the pipeline to absorb any breaks in body production. However, given their size it would take an enormous holding area to stockpile any appreciable quantity. It would also cause hordes of finance types to descend on the manufacturing floor - complete with “wing tips” and  green eye shades â€" to lecture about the time cost of money and all the work in progress.

HTH,
Ralph

[Eric DeVirgilis CLC# 8621]

To better illustrate my question, consider the following data for 1959 Coupe deVille:

VIN#                Body#

139474            21432
139482            21462
139483            21464
139487            21431
139490            21435
139977            21436

My question is why is body number sequence out of sync with production sequence? In the above example, body 21462 car was completed 495 cars before body 21436. Why would this be? For low production models, this departure can be far more radical.

The other part of my question is how did the factory differentiate between, say a 1959 Series 62 Coupe body and a Coupe deVille body since they would be identical (unless the holes were drilled for Coupe deVille scripts or Series 62 front fender crests) at this point?  Did they have separate holding areas for each subseries using the same body shell?

[J. Skelly]

Eric,

If a car was ordered with a special interior, or non-standard paint (such as from a previous model year or a non-GM color), or had seldom ordered accessories, that could explain it.  Also, if there was a parts shortage for one of the accessories, or quality issues with the body, paint, trim or accessory, that could hold it up.  I work at a former GM engine assembly plant.  Engines get set aside if a parts defect is identified, if parts are on backorder, or rework (machining, teardown, reassembly) is required.       

[76eldo]

Eric

I think that they probably had a storage area for bodies and maybe did not pull them in sequential order to get dropped on a chassis.

Could be as simple as newer ones being placed in front of older ones with lower numbers.

Is say it would be odd to have an early vin with a late body or the opposite.

Brian

[Caddyholic]

Eric

were all the vin#s preseated with 59J? for coupe deville

[Richard Sills - CLC #936]

Every '59 Coupe deVille had a serial number beginning with 59J, and every '59 Series 62 coupe had a serial number beginning with 59G.   If the serial numbers were assigned to each car's component parts when the build process began, they would know which bodies were destined to be Coupe deVilles and which were destined to be Series 62 coupes.

[Ralph Messina CLC 4937]

Eric,

Point of clarification: If you are getting these data from the daily production build sheet could you post it without the key numbers. It would be interesting to see how similar they are.

The post by J  Skelly may also be a factor. If body 21436 needed body or paint repair  it could have been recycled and delayed by a day. From a final assembly standpoint it would not make a difference unless the chassis required unique components like air suspension, "Q" engine or Air conditioning. These options are built into the chassis.

[Eric DeVirgilis CLC# 8621]

The build sheet was not very good quality but I'll post it all the same.

I omitted the "59J" prefix from the numbers in the example I posted above as all the VINs belong to Coupe deVilles.

Perhaps J Skelly & Brian are onto something regarding finishing repairs being made to bodies before being placed in final production. I don't see why Special Orders would account for any sequential irregularities.

[Eric DeVirgilis CLC# 8621]

Eric,

Point of clarification: If you are getting these data from the daily production build sheet could you post it without the key numbers. It would be interesting to see how similar they are.

The post by J  Skelly may also be a factor. If body 21436 needed body or paint repair  it could have been recycled and delayed by a day. From a final assembly standpoint it would not make a difference unless the chassis required unique components like air suspension, "Q" engine or Air conditioning. These options are built into the chassis.

Ralph, does the body number include the chassis? I always understood the body was dropped onto the chassis during final assembly.

[Ralph Messina CLC 4937]

Eric,

They only become associated when the body is dropped and the newly assembled vehicle become Cadillac no: 59Jxxxxxx and body YYYY.  If any car has the same  chassis/body numbers sequence  it's a coincident. The final body - chassis marriage is only critical for those cars ordered with options that effect chassis configuration. I don't know the percentage but air suspension and "Q' engine were a very small part of total production. AC cars are another minority percentage. For all the other cars built (except Series75), the chassis would be the same and in effect interchangeable until the body/ chassis marriage when they become a vehicle.

Thinking about our question of Series 62 coupes vs CDV; the bodies start with the same panels and the hole could be punched during stamping or drilled after assembly. In ether case the operation would be done before a  paint color was designated for the body. Making new holes in fresh paint is asking for a rust problem. It's seems to me that the body number would be assigned when the paint is selected.

[Eric DeVirgilis CLC# 8621]

What difference(s) in the body would need to be present in order for a car to be equipped with air conditioning and/or air suspension in 1959?

[76eldo]

i think that the bodies were produced in batches and put in a holding areas D as the orders came in they were used as needed.

The only way to know about the differences in panels that have different ornamentation and corresponding holed would be to hear from someone that has purchased NOS panels and see if they came with more holes for a Coupe DeVille vs a 62 series coupe.

Eldo and Fleetwood panels certainly were different.

The numbers should make sense as far as low to high body numbers matching early to late production.

[Ralph Messina CLC 4937]

Eric,

Not the body, but the chassis. The bodies, from the cowl back, were designed to accept all options as bolt on components. Options not selected may have their location covered by a stamped cover/plate or the location will accept what the lower, standard level of trim would be without sheet metal alteration. The options selected are stamped on the vehicle data plate that shows the body number - assuming it'd stamped correctly. The body number ties back to the production order.

Assuming the body is correctly assembled per the order and had the appropriate AC hardware installed and any lever/switches for the suspension it must mate to a chassis appropriate for those options.   The air suspension requires different control arms to accommodate the airbags; and AC requires a different higher ratio (3.21 vs 2.94) differential ratio for AC.

[wrefakis]

Hello fans !
On the body number question.
Here are 4 Biarritz
169   021675  white buckets
171   023784  so tu tone buckets
174   018059  blue buckets
177   015781  black buckets most common

here there are thousands of cars out of sequence why?

The answer is the order for car production first went to the body plant.
this is why chassis options are not on cowl tag as in air ride,or Q engine.
the completed body with interior and all body options was then shipped from Fleetwood body plant to final assembly
that is when the car was assigned a vin
if a car was a special trim the body would be delayed although already having been assigned a tag number
some times it may have been as simple as being out of white buckets

my 70 dvc last one produced was body 15101 yet they built 15172 vin was 338723 final 70 vin was 338745
this car was built as a favor to the grand nephew of henry Leland based on the condition of the car as delivered I always felt that it may have been a rejected shell used at the last moment as the car had actual repairs done at the plant, but who knows

[76eldo]

That's really interesting. So the fully finished and trimmed body was lowered into a waiting chassis on the line.  I guess some assembly line photos would show that as well.

Bill, I'll look for you at Hershey. I'll be there for a few days.

[Walter Youshock]

You're dealing with two different factories.  Fisher/Fleetwood and Cadillac Clark. 

Bodies were stamped, assembled, wired, upholstered and painted at Fleetwood and sent to Clark. If chassis 5xxxxxxxxx were to have air, be Alpine white and a sedan deville, it had to be mated to an ac engine, trans and rear end chassis for a sedan. The chassis and engine numbers matched as this is what was used as the licensing for the "car", not a body number.  There had to be two different numbering systems used between the two plants.

Furthermore, Clark stamped, painted and trimmed the hood and front fenders and marked them with part of the chassis number, at least in the 50s.  You couldn't have a black Fleetwood body landing on a convertible chassis with white sedan deville fenders being installed at final assembly.

I doubt anyone will really know as so much attention has been focused on Clark and so little on Fleetwood's assembly practices.

It's also doubtful that there was a stockpile of bodies in every color, every interior option and every accessory sitting pre-made waiting for someone to order it.  Like a '59 series 62 4 - window Sdv with manual windows, cruise,  ac and air suspension. 

Every ordered option had to go through the Fleetwood plant first. 

Oddly, though, every option was available as a dealer installation except power trunk as the motor mountings were welded to the body and not amenable to field installation as a bolt-on option like air conditioning or Guidematic.

[Eric DeVirgilis CLC# 8621]

Gentlemen:

Thank you for you input, insights and comments on this question. It would seem there are a number of reasons that could account for these sequence irregularities. Note we haven't even touched on engine number sequence which is another question altogether.

I'll let it slip now the reason behind this questioning: I have just personally seen another 1959 Coupe deVille whose body number is +1 that of my own. The part I found puzzling that the VINs were separated by 487 cars. As I found it practically impossible that not a single 1959 Coupe deVille came off the assembly line after the production of 487(!) cars, I began to realize body numbers are wildly out of sequence relative to final production as indicated by the VIN.

Still, it is intriguing that two near-60 year old sequential body number cars should exist, separated only by 250 miles and.... an online advertisement.    In the end, I felt the condition of the car could not justify the purchase price, unfortunately. 

[Ralph Messina CLC 4937]

i think that the bodies were produced in batches and put in a holding areas D as the orders came in they were used as needed.

The only way to know about the differences in panels that have different ornamentation and corresponding holed would be to hear from someone that has purchased NOS panels and see if they came with more holes for a Coupe DeVille vs a 62 series coupe.

Brian,

Your comment about drilled holes in NOS panels made me curious. I checked the MPL for 59 Series 62 and CDV  quarter panel parts. A note indicates “Drill badge holes necessary” meaning they stocked one style replacement part for collision repair. In production these hole were most likely punched as secondary operations and stored as a component part

Regarding storing bodies; there definitely is a pipeline of bodies including enough to account for production issues. However, GM pioneered the concept of nesting body panels in the 30’s specifically to address space. Body panels were laid out and contoured so they could be stored and transported in a nested stack. When a body is ordered for the production line the panels were pulled, assembled in a jig and welded into a completed body. It then  moved into the body assembly.

Attached is a 13 minute clip showing the complete production cycle for 1957. The story begins at the 3 minute mark. Pay particular attention at 10 minutes for the final assembly information:

https://www.youtube.com/watch?v=XE2ChcaqJLc

[J. Skelly]

Regarding sheetmetal, I doubt GM would stock two types (no-hole and pre-drilled).  It would cost too much.  I recall reading a few years ago about the '68 Impala SS427 models.  If any of you recall, it had three fake louvers on each front fender.  The article mentioned that the holes for the louvers were drilled at the time the car was built.  Hopefully that meant prior to painting.  I would guess templates were available to get the holes in the correct positions. 

Now I wonder about the front fenders of the '71-'78 Eldorado.  Replacement fenders did not have the openings for the monitors when the '71 came out since it wasn't standard equipment.  I wonder if GM was able to justify having two different replacement fenders later on.