Messed up VIN number......

[gregbr]

I'm looking at a 67 shortbed GMC with the following VIN number... CM1570DPC12418A. The truck has a 71/72 4wd shortbed chassis under it, and a 68-72 shortbed, the cab & front are a 67. The truck has been restored by the current owner about 4 years ago and has been put together like this since he got it 6 years ago. The owner said the VIN is on the truck plate and the title. Does this makes sense to anybody??

[widow_maker]

Wow! that vin code makes no sense. Not sure what an M code engine is nor the five digit sequence with an A suffix. There is a letter where the model year should be and I am not aware of a "C" code assembly plant. Overall, there are too many characters in that VIN. I wonder if this could have been a factory re-assignment? That wouldn't explain the mix and match of model year parts though. I saw an auction on Ebay recently (unfortunately I didn't keep a link to it) that was supposedly a factory reassignment as it was converted from 2 wheel to 4 wheel drive which is what this truck has under it. Hopefully some one else can offer some insight into this Frankenstein truck. Best of luck.

[Longhorn Man]

Rod knows the GMC vins better than anyone.
CM1570DPC12418A
C 2 wheel drive
M means V6 gas...a 305 engine.
15 is 1/2 ton

That's about all i can read out of it
I think I remmeber him saying the A is unknown and only shows up once in a great while.

[CE20934]

CM157ODPC12418A

C = 4x2
M = V6 gas
1 = 1500 series
57 = CA dimension (42") {Note: I'm guessing it's similar to Chevrolet's 07 code which is 42"}
OD = Pickup, wide-side
P = assembly plant (Pontiac)
C = 1967
12418 = sequence number (starting at 10001)
A = ?

[Ridgeback]

Hey Greg

I sent you a couple of emails about a SWB for sale did you get them? Thanks.

[gregbr]

CE20934, Where did you find the decode info. I didn't find anything like that.

Ridgeback, Tell me again about the truck. Sorry, but I looked at so many I forget which is which. I'm looking for a 4wd SWB, prefer V8 & auto.

Thanks

[CE20934]

A couple different sources: my 1972 Hollander Truck Parts Edition & 1967 Chevrolet Truck Data Book.

The Hollander did not cover the 57 or the assembly plant, so I consulted the Chevy book. Chevrolet doesn't have a cab-to-axle designation of 57, but the shortbed code is 07, so it was an educated guess. As for the plant, since Chevrolet's P is Pontiac, I'd say GMC's P is also Pontiac.

[Rod]

CE20934 got it right
.....and he assumed correct on the 07 of a Chev being code 57 on a GMC and the lenght from back of cab to rear axle is 42 inch.

The A at the end refers back to GVW range....A for 1/2 ton B for 3/4 ton and C for 1 ton..its actually a little finer measurements than that but its a good method.
A is 6000lbs and less. B is 6001-10000. C is 10001 to 14000 lbs. I use those values for the letters as that's the way it was done on ealier 60's GVW ratings.
Finally may get a break on decoding these now.

[CE20934]

Glad to help.

[gregbr]

Thanks Everyone.

Rod , Where did you find this decode info?? All I found was for 67-72's in the front of a 47-72 Chevy parts book (from dealer), and it didn't cover any VIN's like this one. Why is this VIN different from the standard format... ex ce149j100001 like I have always seen before?

I missed the truck on auction because I thought the VIN had been altered....oh well. Thanks, I know now. Greg

[jamis]

have you guys ever compared cab vins to chassis vin? my chassis vin is one number higher or lower then the cab vin, I can remember which right now . Is that weird (my cab cut inline at the assembly plant) or all the all like that.....

[Rod]

I get these decoding abilities via ..Hollander Manuals..GM Data Books, GM parts book, and familiarity......uh...expert ability

So C20934..if you had a parts book you could look up front in vin decoding pages and see the GMC and Chev differences on those 07 means same a GMC 57 number etc. They pretty much go upward in the same fashion...09 Chev means 59 GMC
11 Chev means 61 GMC...threw that in so you can figure out where it climbs over. Its just plain odd why those number dont actually mean the measurement. Example meaning 07 refering to 42 inches from cab to rear axle. It might have somthing to do with reference points in the drawings. I know when I look at drawings/ blueprints sometimes that a way its done. I'll look at a couple books to see if that works.


The reasons why its done that way? Well GMC did do things different than Chev...for whatever reason. They copy each other exactly in other ways. The Canadian made GMC's are more typical to have different GMC vins...so when you figure you have an assembly plant of code number 1 , that an Oshawa Canada built truck. This Pontiac Assembly plant must be to close to the Canadian Border.. they musta drank our beer.
That assembly plant has produced vins like this also...so it's not just a Canadian built thing.. its a GMC built thing. I haven't seen a Chev vin produced in this way.. I dont think anyone asked me to decode anything like that which was related to a Chev.

The only real years anyone has trouble decoding on GMC's are 67, 70 and 71. As they did them a little different. I dont know how to make a vin decoder that you enter values in, but it could be done if you had the correct values entered in the formula patterns.

Its pretty common for GMC 1967 vins to has a 9 as the second digit of vin also ..it distinguishes them as built in Canada also.
So you would get C9S14110002

drop the 9 as you know its a Canadian built GMC and it decodes in the vin decoder.


jamis have heard of that on here before also. Probaly built on Monday after Long weekend.

gregbr...it looks like the truck you were looking at was a short wheel base former V6 2wd 1967 truck body put on a 71-72 4wd short wheel base frame.

[widow_maker]

Sorry - I was looking in my Chevy book for a "GMC" code - of course it won't make sence!! I need to read a little closer before I respond. Sometimes I can be such an idiot!

[gregbr]

Thanks for the help, wish I had this info a couple days ago.....I will look for a GMC book. My 70 GMC has the standard VIN ce147......I forget, but it's not like that messed up one. Thanks again for the great help.

[CE20934]

Originally Posted by Rod

Its just plain odd why those number dont actually mean the measurement. Example meaning 07 refering to 42 inches from cab to rear axle. It might have somthing to do with reference points in the drawings. I know when I look at drawings/ blueprints sometimes that a way its done. I'll look at a couple books to see if that works.

It could be that. I really don't know. It would make sense, seeing as there's a pattern here.

07 = 42"
09 = 54"
{skip a few}
17 = 102"

There are a few oddballs:
20 = 120" or 124"
23 = 138" or 143"
28 = 211 1/2"

This Pontiac Assembly plant must be to close to the Canadian Border.. they musta drank our beer.

Pontiac Truck & Bus Assembly is in (oddly enough) Pontiac, MI, which is about half-an-hour from the Ambassador Bridge to Windsor, ON.

Fine beer in that province too.

[gregbr]

OK, now that I'm home where my numbers are. My 70 GMC has the following numbers...VIN CE134BZxxxxx (only 5 digits) and glove box sticker has model CE15734. I have the original build sheet and glove box sticker and all paperwork matches the truck. How do these decode.....Please.

I have a Chevy parts book (dealer book), is there a GMC parts book also??

[CE20934]

GMC Dealer books exist (Rod has at least one), but the trick is to find them.

[CE20934]

Wait, forgot to decode.

CE134BZxxxxx

C = 4x2
E = V8 gas
1 = 1500 series
34 = Pickup, wide side
B = Baltimore Assembly
Z = 1970
xxxxx = serial number (starting at 50001)

CE15734:

C = 4x2
E = V8 gas
1 = 1500 series
57 = 42" CA dimension (short bed)
34 = Pickup, wide side

[gregbr]

Thanks ce20934!! I will be looking for a GMC parts book.

[Rod]

ce20934 got it right for gregbr also.