factory grease pencil marks?

[bruceman1968]

Originally Posted by Keith Seymore

Negative. They had probably already built several hundred thousand vehicles so the full sequence number might be something like 299902, but they just wrote the last two or three digits on the various components for tracking purposes. The full build sequence number just keeps climbing all model year as vehicles are built, but in this way you could be building vehicle 901, 902, 903, 904 etc. one day and then 001, 002, 003, etc the next. (Full sequence would be 299901, 299902, 299903, 299904,etc; 300001, 300002, 300003, etc).

My truck was built on Monday Sept 29 of 1986 (in Flint) and the VIN was already up in the 317000 range (60 jobs per hour, two shifts); similarly my Chevelle was built in September of 1973 in Oshawa and the VIN is also already up in the 300000 range.

K

Keith, Are you saying that the 902 number is the last 3 digits of his VIN number?

[Keith Seymore]

Originally Posted by bruceman1968

Keith, Are you saying that the 902 number is the last 3 digits of his VIN number?

Nope. There is no direct linkage between the build sequence number and the sequential portion of the VIN.

The build sequence number absolutely increases one-for-one for every truck built. So at the beginning of the year you start with truck "01" and start counting, all the way to 700,000 or every how many trucks were built in that plant.

The VIN sequence portion does not increment one for one....nor are trucks necessarily built in VIN order. In my day Chevy's started with 100001 and GMCs with 500001 (and then Cadillacs with 600001); so, while within a nameplate the VINs increment up one by one but because the various nameplates are jumbled in during the day's production run the VINs do not increment up exactly one for one overall.

Let's say your daily build looked like this (I'm making this up for illustration purposes):



PVI = "Primary Vehicle Identifier" - and is the way the cab/box are identified in body shop, before the GA (General Assembly/Final Line) sequence number and VIN are even created. There are two opportunities for the build order to be shuffled: coming out of body shop into paint, and coming out of paint into trim/GA.

GA sequence number is the order in which the trucks go down the final line. Once they hit trim/final the build order is locked in.

In the example shown here the operator would write the "901", "902" etc (or even just "01", "02") on the front of dash, rather than the full "299901".

Does that help?

K

[Keith Seymore]

So - the purpose of the above example was to show what the "902" means.

But - there are some other nuances buried in there, that I put there on purpose, that I would like to discuss briefly:

a) Vehicle order numbers: those are real live actual dealer order numbers. That's how they look in terms of alphanumerics, and in order (all jumbled up). I've never seen any kind of rhyme or reason (or intelligence) in how the order numbers are constructed.

b) PVI - is the primary tracking number prior to GA and is established after the dealer order number is received at the plant and released for production. The vehicle cabs and boxes were built in PVI order through the body shop but shuffled going into paint, due to repair, rework or part availability.

c) GA sequence - the cab and box get shuffled again, coming out of paint before dropping into trim/final. This is again due to any repair or rework or part availability, but additionally to balance the workload for the people in trim and final. Said differently, you can't have too many air conditioning, manual trans, cab roof marker lights, dually boxes, etc (high work content) vehicles in a row. Gotta spread 'em out a bit.

d) Notice how the VINs increment up one by one within a brand. That is not always the case but I have left it that way for the purposes of this example.

e) Notice how there is a GMC every 9th or 11th job, and a Cadillac every 20th job. That was intentional. The VIN sequence reflects the production volume of that brand built, too, ie: at this point 200,000 Chevy's have been built (317388 minus 100001), but only 20,000 GMCs (521102 minus 500001) and only 10,000 Cadillacs (610101 minus 600001).

f) Those vehicle owners are for pre-production internal users. For regular production that would be the actual ultimate customer (Keith Seymore, or Bruceman, or DavisChevy, etc)

Just a reminder: on my truck the GA build sequence number was "87" but my VIN ends in "317388".

K

[NC_John]

Keith- thanks for all the info- that was a great tutorial!

[bruceman1968]

Any chance the 902 number refers to the PVI number or vehicle order number, instead of the GA number? From your last post it sounds like the GA number isn't known until the assembly process. In the research I have done, that number shows up before the assembly process. I have documented that number showing up during the stamping of the pieces used to make the truck. Here is a example.









I took this pic and the stamped number is 214


I have documented several trucks with the stamped number matching the grease pencil number. Any light you can shed on this would be greatly appreciated. I have used the info you provide in your posts a lot to help me do this research. you are a most valued resource. Thank you for all the knowledge you share with this board. We need more assy line guys on here.
P.S. I love the story of how you followed your truck down the line. To cool

[Keith Seymore]

Originally Posted by bruceman1968

Any chance the 902 number refers to the PVI number or vehicle order number, instead of the GA number? From your last post it sounds like the GA number isn't known until the assembly process. In the research I have done, that number shows up before the assembly process. I have documented that number showing up during the stamping of the pieces used to make the truck. Here is a example:

Thank you -

Yes - good examples - in the examples you have posted it looks like the trucks were built "straight through", meaning the PVI (not the dealer order number) and the final line GA sequence number were the same. No shuffling occured after body shop or after paint. The stamped portion was done in body shop after the cab was welded up and then the grease pencil after paint.

Were those Fremont trucks, perhaps? Fremont built straight through (no shuffling).

Re: Following my truck down the line: I wish now I had kept some of the paperwork (the build manifest, build sheet, inspection paperwork, etc) from that day but I didn't even think of it until recently. I actually followed two of my own personal trucks down the line for fun - but now I follow preproduction builds down the line for a living.

Originally Posted by bruceman1968

We need more assy line guys on here.

Probably not; then we would just argue with each other...



K

[bruceman1968]

Originally Posted by Keith Seymore

Thank you -

Yes

Were those Fremont trucks, perhaps? Fremont built straight through (no shuffling)



K

Two of them are Fremont trucks for sure. The 3rd one probably is to, I don't have a VIN on it.
All the trucks I have documented so far (with a grease number and a stamped number) have been from Fremont. Even have a GMC.
Thanks again Keith, your responses really do shed a lot of light. I appreciate the help.