The build date project

[Keith Seymore]

(I can't believe I haven't mentioned this yet, but):

Now would be a good time to remind you all that trucks were not necessarily built in VIN order.

Most plants had an accumulator, or body bank, between the cab shop and paint, and then again between paint and the trim line.

This allowed for a reserve of bodies to be drawn to keep the final line running in the event of a breakdown or stoppage in the cab shop or trim (which was often) and also for the shuffling of builds based on downstream workload leveling. For example, you can't have too many four speeds in a row, or too many A/C jobs in a row, or too many cab high running lights in a row, or too many dually's in a row, etc. It also allowed one to shunt a vehicle off to the side for an extended sheet metal or paint repair before shipping it on.

Fremont is one of the plants that did not have that. Risky move, but once the VIN was established the vehicles presumably stayed in that order all the way though (barring some catastrophe).

Flint - not so much. Vehicles could be shuffled around, shuttled off to the side and delayed by a day or two.

I would encourage you all to put a mental day or two around any published date. Although they are written in ink they are not necessarily written in stone.

K

[402Bowtie]

Originally Posted by Keith Seymore

(I can't believe I haven't mentioned this yet, but):

Now would be a good time to remind you all that trucks were not necessarily built in VIN order.

Most plants had an accumulator, or body bank, between the cab shop and paint, and then again between paint and the trim line.

This allowed for a reserve of bodies to be drawn to keep the final line running in the event of a breakdown or stoppage in the cab shop or trim (which was often) and also for the shuffling of builds based on downstream workload leveling. For example, you can't have too many four speeds in a row, or too many A/C jobs in a row, or too many cab high running lights in a row, or too many dually's in a row, etc. It also allowed one to shunt a vehicle off to the side for an extended sheet metal or paint repair before shipping it on.

Fremont is one of the plants that did not have that. Risky move, but once the VIN was established the vehicles presumably stayed in that order all the way though (barring some catastrophe).

Flint - not so much. Vehicles could be shuffled around, shuttled off to the side and delayed by a day or two.

I would encourage you all to put a mental day or two around any published date. Although they are written in ink they are not necessarily written in stone.

K

Yes, I think we/I have come across a few potential examples of what you are referring to with perhaps some sequencing nuances. Some examples: 0A135688, 1Z639337, 2J160173, and 2Z109XXX.

[Keith Seymore]

Originally Posted by 402Bowtie

Yes, I think we/I have come across a few potential examples of what you are referring to with perhaps some sequencing nuances. Some examples: 0A135688, 1Z639337, 2J160173, and 2Z109XXX.

The General Assembly Sequence Number is really what we want for this.

But it was not necessarily preserved or available, so we use the VIN for the next best approximation.

It's funny but nobody in the assembly plant cares about the VIN. It's just another part to be put on the correct vehicle, like a tune up label or Mulroney window sticker or SPID. The GA sequence number is the gold source when referring to a particular build.

But, once it leaves the plant, it's all about the VIN. Because it's all they know and have access to, typically.



K

[Getter-Done]

Originally Posted by Keith Seymore

The General Assembly Sequence Number is really what we want for this.

But it was not necessarily preserved or available, so we use the VIN for the next best approximation.

It's funny but nobody in the assembly plant cares about the VIN. It's just another part to be put on the correct vehicle, like a tune up label or Mulroney window sticker. The GA sequence number is the gold source when referring to a particular build.

But, once it leaves the plant, nobody out in the world cares about the GA sequence number. It's all about the VIN. Because it's all they know.



K

Worked at an Assembly plant for 17 years.

Yes, The Sequence Number is all the Mangers went by.

Mostly to track defects and make repairs.
I work in Trim then the engine line, then Paint.

They were all Worlds apart on how the vehicles were in order.

The more vehicles produce an hour the less parts the technician would have to put on the vehicle.

With these Trucks being run at 30 something units an hour,
The person probably installed several parts on the truck at their job station.

That would be a little under a 2-minute line speed.

[402Bowtie]

Originally Posted by Keith Seymore

The General Assembly Sequence Number is really what we want for this.

But it was not necessarily preserved or available, so we use the VIN for the next best approximation.

It's funny but nobody in the assembly plant cares about the VIN. It's just another part to be put on the correct vehicle, like a tune up label or Mulroney window sticker or SPID. The GA sequence number is the gold source when referring to a particular build.

But, once it leaves the plant, it's all about the VIN. Because it's all they know and have access to, typically.



K

Originally Posted by Getter-Done

Worked at an Assembly plant for 17 years.

Yes, The Sequence Number is all the Mangers went by.

Mostly to track defects and make repairs.
I work in Trim then the engine line, then Paint.

They were all Worlds apart on how the vehicles were in order.

The more vehicles produce an hour the less parts the technician would have to put on the vehicle.

With these Trucks being run at 30 something units an hour,
The person probably installed several parts on the truck at their job station.

That would be a little under a 2-minute line speed.

Some questions for both of you:
1) The sequence number is in on the top left of the build sheet, above the date, correct?

2) At what point is the build sheet printed with the serial number? It seems like the serial number would have to be included fairly early in the process or otherwise perhaps printed on the build sheet after some assembly has been completed?

3) Pretend I have two build sheets. One is sequence number 17647 (w/ s/n 2Z120845) and the other is sequence number 17699 (w/ imaginary s/n 2Z120897) and they both show a 11/12/71 build date. I think you are saying that is 100% safe to assume that sequence numbers in between those two were built on 11/12/71. However, at some point along the way, one of the sequence numbers could have been assigned a serial number outside the range of 2Z120845 and 2Z120897, or at least in a non-consecutive manner. Is that correct?

4) For 100 consecutive sequence numbers, how many of those trucks are likely to have consecutive serial numbers?

Maybe I'll start trying to include sequence numbers. Any other sources for the sequence number besides the build sheet? Firewall? SPID?

[Getter-Done]

Originally Posted by 402Bowtie

Some questions for both of you:
1) The sequence number is in on the top left of the build sheet, above the date, correct?

2) At what point is the build sheet printed with the serial number? It seems like the serial number would have to be included fairly early in the process or otherwise perhaps printed on the build sheet after some assembly has been completed?

3) Pretend I have two build sheets. One is sequence number 17647 (w/ s/n 2Z120845) and the other is sequence number 17699 (w/ imaginary s/n 2Z120897) and they both show a 11/12/71 build date. I think you are saying that is 100% safe to assume that sequence numbers in between those two were built on 11/12/71. However, at some point along the way, one of the sequence numbers could have been assigned a serial number outside the range of 2Z120845 and 2Z120897, or at least in a non-consecutive manner. Is that correct?

4) For 100 consecutive sequence numbers, how many of those trucks are likely to have consecutive serial numbers?

Maybe I'll start trying to include sequence numbers. Any other sources for the sequence number besides the build sheet? Firewall? SPID?

Keith would be the main one to Verify these Questions.
That pertain (Directly to These Trucks)

I will give my input from the experience,
I had at another Auto manufacturing plant from 1992-2010.

Yes, it was a foreign plant and there is a 30-year gap.
Somethings will still apply.

I thought I knew a lot about vehicles till I worked there.

I had no idea how they put these together the way they do.

Okay First question: I will say Yes.

When I worked in the Paint Plant,
I worked in the sealer department.
One of my jobs was to put (tape) the
Broadcast (Build) sheet on the front door.

The vehicle had just moved thru the Bake oven after being Phosphate(Dipped) coated.

I paid attention to the Serial Numbers (Because I am a Car Guy)
They would be some missing every once in awhile.
I asked WHY?
They would get pulled to the side in Body shop/ stamping plant.
Then they got filtered back in.

Okay keep that train of thought.
I did not work where the were painted.
But I did sneak in there to see what was going on.

So now When I worked in the Trim section.
I seen the final results of the paint Plant.

For 1 or 2 of the years of employment I worked in Zone 1
I also tape a Brodcast (Build) sheet on the door when the car dropped down from paint.
Because they had to remove the other one to Paint the door.

This is where they dropped straight in from being painted.
There was a big (Corral) area Before that,
This is where the cars got sorted out,
as Keith spoke of. Because of trim levels and options etc.

As a technician , A person had more parts to put on an AC truck verses a Non/Ac truck.
If you had to build 4 of these Ac/Trucks in a row you would have to shut the line off.
Which stops Production.

So, this type of sorting (Messed the order of the serial # Up).

With my insight of this experience, I had at that plant.

The cab and frame would be the biggest factor of the order of this situation.

Because the serial # would be determined then.

If something happened after that,
It may change the sequence number.

[Keith Seymore]

Originally Posted by Getter-Done

Worked at an Assembly plant for 17 years.

Originally Posted by Getter-Done

I did not work where the were painted.
But I did sneak in there to see what was going on.

40 years for me; across about a dozen different GM assembly plants (Flint, Pontiac, Ft Wayne, St Louis, Janesville, Oshawa, Fremont, Arlington, Silao, Wentzville, Mishawaka, Hamtramck come to mind), three or four pre-production shops and one skunk works (that I can't talk about).

I've been thinking about writing a thread about "How I got so Smart", or something like that, but in a nutshell: it's "sneaking".

Even before I started my engineering curriculum at Flint I had a stint in Personnel. One of my jobs was to deliver the mail. As a result, one learns not only where all the "monuments" are in the plant, but three or four ways to get there: front ways, back ways, sneaky ways, etc.

While you are sneaking around you are getting to know folks and learning about their jobs, and learning about the process, by osmosis.

Even after that, as an "adult" when I would go to these various other plants for new model launch, I would ask my plant host to show me around ("...show me where you put the VINs on", or "...show me the paint body bank", or "take me out to paint repair") to further my understanding. They were happy to show off their place and I was genuinely interested (that is, I was not being manipulative to curry favor).

Or - I would sneak around myself. I remember the first time I went to Wentzville they pretty much got me through the door and said "ok - we'll see you in a week". I had been there for about 10 minutes before they cut me loose to fend for myself, so - after finding where I was going to be working - I spend the rest of my time watching trucks get built and wandering around.

There is no shortage of things in a vehicle assembly plant to capture your imagination, if you are a car guy.

K

[Keith Seymore]

Having said that, I'll take a swing at these:

Originally Posted by 402Bowtie

Some questions for both of you:
1) The sequence number is in on the top left of the build sheet, above the date, correct?

Normally it's specifically labeled, but yes.

Originally Posted by 402Bowtie

2) At what point is the build sheet printed with the serial number? It seems like the serial number would have to be included fairly early in the process or otherwise perhaps printed on the build sheet after some assembly has been completed?

Early in the process, like before the build is started. All of the build sheets and manifests are printed and distributed a day or so before the build starts.

Just to be clear: to me "serial number" = "sequential portion of VIN"

Originally Posted by 402Bowtie

3) Pretend I have two build sheets. One is sequence number 17647 (w/ s/n 2Z120845) and the other is sequence number 17699 (w/ imaginary s/n 2Z120897) and they both show a 11/12/71 build date. I think you are saying that is 100% safe to assume that sequence numbers in between those two were built on 11/12/71.

Sequence number = Yes. By definition. Because even if you have re-ordered the VIN/Serial numbers the new build sequence numbers are still going to count up one by one

Originally Posted by 402Bowtie

However, at some point along the way, one of the sequence numbers could have been assigned a serial number outside the range of 2Z120845 and 2Z120897, or at least in a non-consecutive manner. Is that correct?

Yes. Although in this case it is the VIN/serial number that exists and is assigned a new sequence number (not the other way round).

Originally Posted by 402Bowtie

4) For 100 consecutive sequence numbers, how many of those trucks are likely to have consecutive serial numbers?

Depends on the plant (because of the accumulators and buffers, and lack thereof).

Fremont - 99%
Flint - 60-80%

Originally Posted by 402Bowtie

Maybe I'll start trying to include sequence numbers. Any other sources for the sequence number besides the build sheet? Firewall? SPID?

Firewall - yes. Any place where components were assembled off line and conveyed in sequence to the main line: Front end sheetmetal, radiator support, grille, axles, tire/wheels, seats, etc. But - it will typically be the last two or three digits of the sequence number, in a form of shorthand. Not the full six digits of the full sequence number.

SPID - no. The sequence number does not appear on the SPID

K

[Keith Seymore]

Originally Posted by 402Bowtie

3) Pretend I have two build sheets. One is sequence number 17647 (w/ s/n 2Z120845) and the other is sequence number 17699 (w/ imaginary s/n 2Z120897) and they both show a 11/12/71 build date. I think you are saying that is 100% safe to assume that sequence numbers in between those two were built on 11/12/71. However, at some point along the way, one of the sequence numbers could have been assigned a serial number outside the range of 2Z120845 and 2Z120897, or at least in a non-consecutive manner. Is that correct?

At the risk of overdoing let me try a different approach.

We are talking about the relationship, or lack thereof, between the build sequence number and the VIN/serial number.

Vehicle orders are sent from Central Office to the plant in a strange six character code (see below). The order number is the tracking mechanism until the PVI, or Primary Vehicle Indicator, is established. The PVI is pulled in a sequence and are used to identify the vehicle until the VIN is established. The serial portion of the VIN is also pulled in sequence.

These can be broadcast to cab shop at the start of build and maintain pretty much this order. However, here is where the fun starts:

The vehicle/VINs can get shuffled after cab shop before paint, and again after paint but before trim but the build sequence number still counts up one by one.

In other words - there is a unique cab shop sequence counting up one by one, and then a unique paint shop sequence counting up one by one, and then comes the final line (General Assembly) sequence number counting up one by one - the one everybody cares about.

I didn't want you to think that the GA build sequence number is jumping around. It is not (barring some catastrophe where a vehicle needs to be pulled completely from the system and reinserted later).

The best analogy I can think of is writing checks: you write the checks in sequential order - pretty much always - but they do not necessarily clear the bank in that order.

The PVI and corresponding VIN/Serial numbers are pulled sequentially - but they do not necessarily clear the end of the line in that order.

K

[Keith Seymore]

Originally Posted by Getter-Done

The more vehicles produce an hour the less parts the technician would have to put on the vehicle.

With these Trucks being run at 30 something units an hour,
The person probably installed several parts on the truck at their job station.

That would be a little under a 2-minute line speed.

This is correct -

A guy might have a "main job" like "Fender Set", or "Spare Tire Hang", or "Battery Install" but after they complete that part there are little wires to connect or route; other small things to fill out those extra few seconds.

K