# transmission and differential coding



## David C Hall (Dec 28, 2021)

Is there somewhere to look on the tags to find the transmission and differential that originally came in the car??


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## BLK69JUDGE (Jun 10, 2010)

Welcome ...

it often helps to post the year and model of your Pontiac ....
also engine and transmision rear diff info really helps too

automatics have a tag 2/3rds back on the passenger side just above the pan seal line
clean gently if the paint scrubs off easily with chemicals...

sometimes just taking a picture and blowing it up is best for preservation porpose.
there will be a painted letter code and a stamped info on the bottom edge
67 n up ?

4 speeds there could be a tag hanging on the side cover,,,,
or research the stamping usually on the passenger side.case
at the back vertical at the midplate ,,, lotso f info on line

rear differential ,,,,,looking at the cover 5 oclock and 7 oclock positions there are
numbers cast into the housing

also depending on the year and model there is a stamp on the axle tube
for originaly built ID ,,,, info on the internet depending on your
housing information


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## O52 (Jan 27, 2019)

Transmissions from 68 and up had the VIN stamped on the case. 
The rear axle did not so the next best indicator of originality would be the the casting date and axle code would usually be within 6 weeks prior to the vehicle build date.


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## GtoFM (Mar 23, 2018)

On my '64, the 4spd trans has the tag attached to a side cover bolt, however that is just the p/n which should be correct for the year. The VIN stamping is on the case top, front, passenger (RH) side. It can be read from the engine bay using a flexible mirror and not so flexible body.👴 
The diff. info is stamped, as noted, on the RH axle tube directly under the brake line brkt. (P 3.23 L)


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