Found two build sheets under my seat…help Keith Seymore

[Corts60]

So I just bought a 54k mile '78 Silverado and I found the build sheet under the seat. I was so excited! But then I found a second one, that was for a completely different truck. What's the deal?

This one is for my truck:

This one is for a 1978 GMC Jimmy with a 400:

[mrolds88]

On occasion these things happen. I got a 64 olds that had a build sheet from another car and not the right one for it. But from the looks of things, you got a build sheet for a K5 Jimmy that was white and a red interior. Would be cool to find the owner of that one.

[mgchevyparts]

usually the next one in line

[Corts60]

Originally Posted by mgchevyparts

usually the next one in line

That would make sense. I don't know how to read these things so hopefully someone can chime in and let us know how that assembly line works….

[Axle]

Technically, they are considered garbage after use. Some big shot may have been walking the line at that station so the guy pulls the sheet, and tosses it in the next car down the line when 'the coast is clear'. Or any other number of reasons the sheet ended up in someones hand and then chucked in the next convienient car down the line.

Alex.

[80SPORT]

One of my duallys (1980) had a blazer build sheet under the seat as well as the one for the truck.

Yours has a couple of interesting options...the PA6 wheels and ZY5 2 tone.
Not sure what the D88 sport stripe is unless it is the hood stripes??

[Corts60]

I think it is for the hood stripes as well.

[Keith Seymore]

First of all, thank you for posting those. I love 'em and could look at them all day.

You guys are correct. The build sheets are to help facilitate the assembly process and are meant to be pitched after the truck is done. I've watched several million build sheets get thrown away at the end of the line. Build sheets that are stuck in the seat cushions or on top of gas tanks (or under the carpet) get left there because it's easier to leave them where they lay than to remove them and throw them away.

So - since they are not a controlled document it's possible for them to get in the wrong vehicle, either because someone got out of sequence or because someone removed a build sheet and threw it back into the wrong vehicle.

If you look at the schedule date/ sequence in the upper LH corner these two trucks do appear to have followed one right after the other (18-2828 and then 18-2829). Notice that, in spite of that, the sequential portion of the VINs are dramatically different because Chevy and GMC had separate VIN sequences (Chevy started at 100001 and GMC started at 500001).

K

[Keith Seymore]

Originally Posted by Corts60

That would make sense. I don't know how to read these things so hopefully someone can chime in and let us know how that assembly line works….

I am happy to answer any specific questions you might have.

K

[Axle]

Did GM sequentially assign vins as they went/go down the line?

At the local ford plant, the vins are not sequential, but a "lottery" of sorts where the vin is assigned ahead of time and has no bearing on assembly sequence.

Alex.

[Keith Seymore]

Originally Posted by Axle

Did GM sequentially assign vins as they went/go down the line?

At the local ford plant, the vins are not sequential, but a "lottery" of sorts where the vin is assigned ahead of time and has no bearing on assembly sequence.

Alex.

Basically, no.

For us it varies by assembly plant.

Some plants assign the VIN early in the process and build straight through. Those are in the minority.

Most plants have a "bank"/accumulator after the body shop and then again after paint, with multiple "lanes" to input vehicles and draw vehicles from. There is no "first in/first out" relationship. That gives two opportunities to shuffle jobs prior to pulling them for final assembly, based on work load balance, part availabililty, extended repair etc.

Additionally - there are often separate VIN sequences for nameplate (Chevy vs GMC, or Pontiac/Buick/Olds) and sometimes even engine type (V8 starts at 100001 but 6 cylinder starts at 600001). So - based on these constraints the VIN sequence can be dramatically different for two vehicles following each other down the line, as shown here.

K