Motor Serial Numbers

[Mulana]

Howdy everyone: I was under the impression that the motor serial numbers included the date of manufacture and CID. I cannot figure out mine... 432000796.

Thanks for your help.

[BillT]

It's either a co-incidence or you have a 432.

Do you know if the engine is approx a '74 or '75?

[Funky61]

BiilT is correct;

Here are some samples of engine stampings for a 379 and 401. I am not sure what the other numbers refer to.

[Mulana]

I honestly don't know what year my motor is... I bought off the self at a used truck yard. The fella there showed me how to read the numbers on the other V6's, and they included the CID, month, day and year. But on mine, that didn't work. Obviously, I know I have a 432. The motor sat on the shelf for so long it got lost and the inventory information disappeared. No clue to the year or what it came out of.

[James]

Originally Posted by Mulana

No clue to the year or what it came out of.

Look at the casting date on the intake and exhaust manifold.

[LEWISMATKIN]

your engine serial number indicates first that it is a 432. the balance of the number indicates that this is the 796th engine built in this displacement. According to the paper titled "the first century of GMC trucks" P.33 stated that all gmc V-6 engine production ended with the end of the 1973 model year run. I know that this is incorrect because i personally know of at least 3 c-series trucks built in the 1974 model year production with GMC V6 power. two were 379's and one was a 305c. I believe your engine is a 1973 year production.

[Mulana]

Thank you for the reply. This makes the most sense.