700r4 code

[pat moran]

I have looked and looked for a chart that can decipher the vin on my 700r4.
The vin is 0CHM212B
here is what I know (I think)
0 = 1990
CH = ? What model/vehicle
M = 700r4
212 = 212 day of 1990
B = plant shift of build
Any one out there have a chart that tells what the “CH” is? (Sorry mom bad grammar)
Thanks in advance

 

[Matt69olds]

That’s probably a calibration code. At one time there was probably a sticker somewhere on the bellhousing with those same numbers.

The calibration code tells the people on the assembly line what color accumulator springs to use, which valve body and spacer plate to install, what extension housing to bolt on, etc.

A corvette transmission would get a different valve body than would grandmas Cadillac. A 6.2 diesel transmission would have different shifting characteristics than one for a 2.8 V6.

I work in a Big 3 factory. All those paint dabs, number stamps, and marks on engines and transmissions mean something to someone.

If you look in a factory service manual, you can probably figure out exactly what that code means.

 

[Jgonick]

A little late, but maybe it will help someone in the future.

CH is model number/application. Staring 1986 they added an extra digit "M" for 700r4 and later on "D" 4L60E

ATSG THM 700-R4 "UPDATE HANDBOOK" Gives information about model/application and internal wiring starting around page 99.

You can find this manual online if you search. Currently it can be found here-(there is a download button under the pdf file in the grey if you hover your cursor over the pdf)
Link