VIN Discrepancy

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headgasket13

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Ontario
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John
Truck Year
1981
Truck Model
C2500
Engine Size
350
Hello everyone, I am in need for assistance. I have purchased a 1981 GMC C2500, 2 months ago, I have already got it appraised (necessary for vehicles over 25 years old in Ontario to get them registered) and got it registered through ServiceOntario (Ministry, similar to DMV in the US). I just realized that the dash board vin has a '3' in the 6th digit, and all of my paperwork and ownership has a '2' instead. All other characters in the vin's match. I have read online that this 6th digit is the identifier for whether it's a 1-ton ('3') or a 3/4-ton ('2'). My truck was assembled in Oshawa, Canada. I have tried online decoders on my paperwork vin (with the '2') and all the information matches my truck's spec. Also my SPID sticker in the glovebox is gone. Where else can I check the vin locations to verify the trucks true identity? My guess, is that either its a 45 year old ministry typo or a Oshawa assembly typo. My question, is this going to be a problem for passing safety inspection and insuring the truck, selling the truck? What should I do next? Please help me out. Thank you.

 

Keith Seymore

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Here is the VIN structure for 1981:

You must be registered for see images attach

Your interpretation is correct about the sixth digit.

There will be a partial VIN stamped in the top surface of the top flange of the frame rail. You will likely need a small mirror to see it.

Oshawa is also the only squarebody assembly plant to stamp a VIN or partial VIN on the firewall behind the heater box.

Good luck -

K
 

Keith Seymore

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You could also contact GM Of Canada and ask them for the original invoice for your truck. My guess is that they would work with you to determine which VIN is correct and which VIN does not exist.



K
 

78C10BigTen

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Ted
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1978
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Here is the VIN structure for 1981:

You must be registered for see images attach

Your interpretation is correct about the sixth digit.

There will be a partial VIN stamped in the top surface of the top flange of the frame rail. You will likely need a small mirror to see it.

Oshawa is also the only squarebody assembly plant to stamp a VIN or partial VIN on the firewall behind the heater box.

Good luck -

K
I just learned somethin, thanks Keith!
 

Keith Seymore

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There will be a partial VIN stamped in the top surface of the top flange of the frame rail. You will likely need a small mirror to see it.
Giving this further thought: the partial on the frame is not going to help. The format is model year, assembly plant and the serial portion of the VIN, like

B15xxxxx, where
B = model year, 1981
1 = Oshawa
5xxxxx = serial portion

so no indication of model or series type.

Your best bet is either the VIN on the firewall, if it is a full VIN, or the guys at GM of Canada.

You can also do the GM Heritage Center archive here in the US, but they are the larger organization and therefore less likely to want to mess around with it. GM of Canada is a smaller organization and might be more willing to work with you (and more polite about it, eh?).

K
 

75gmck25

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Over the years I’ve read that there are differences in the one ton frame, so it is not identical to the 3/4 ton and 1/2 ton. I would research the differences and compare it to your truck. For example, I think the rear shock mounts are different on a one ton, which would be easy to check. IIRC, there are also slightly different dimensions for frame height or thickness.

Once you determine what you have, in my state you just apply for a corrected title. I had to do it for my ‘75 because they misinterpreted my handwriting when I changed state registration and my title said I had a ‘78.

I think you want the title to match the frame, since the suspension and drivetrain define the real capability of the truck. Swapping cabs to get one that is rust-free is fairly common, so maybe that happened. One catch in the US is that the dash VIN is usually the definitive source if there is any question of theft or fraud. Changes must be properly documented to avoid problems later.
 

goldpack

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350 with 350 3 speed
a couple months back I was looking at a a square in a parking lot.
I took a pic of the New York State registration sticker to run the vin.
(just because it looked so damn sweet)

it was a 2wd half ton cab, = the cab makes the registration,

the truck chassis was a 3/4 4wd short bed (and it had a snow plow)

so when cobbling together a antique pickup truck from several wrecks,...the thing needed is a clean title for the cab used with its vin # in on it.

(this was a rather nice looking thing...way to nice to be plowing salted snow...so I guess when rebuilt it was all sealed up,....and I hope it does plow work on a long driveway ...to keep away from the municipal salt. If I were ask the owner I would think the original cab had a tree land on it, and a half ton 2wd with a clean title was what was found....

in New York,...anything 25 years older gets a annual safety inspection at a local private garages,.. things that are "rebuilt", get a special 1st inspection from a state owned garage with state personnel, looking for stolen parts..... so a vehicle rebuilt locally in the state, or one imported from another state, gets such....
 
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