GMC engine serial numbers do not seem to be well documented as to their correlation to particular production years. 228 engines were used from 1939 to 1952 according to the sources I read.
I am presuming that you know that the first 3 numbers of your GMC engine serial number indicate the displacement and your number could be preceded by the letter 'A' through 'G' , then 228 and then the serial production number. I found no sources that tied the engine serial number to a particular year.
In searching the
http://www.oldgmctrucks.com/ site, I ran across a post from SlimSix, the engine technical advisor which may prove helpful.
He stated that the Date Casting Code, usually found on the same side as the block casting code can be used to narrow your possible production date.
It looks like a small raised plate with two screws and has a letter A-L which corresponds to Jan-Dec, a number 1-31 which is the day, and then a single digit which signifies the last number of the year.
So "B 28 6" would signify February 28, 1946 on a 228 engine. Your problem will be if your last number is "9" "0" "1" or "2" because each of those numbers could stand for two different years. 1939 or 1949, 1940 or 1950, etc.
A last digit of "3" through "8" could only signify one year because of the 1939-1952 production of the 228.
Join the oldgmctruck site if you still can't id your engine year. Some of the people there will forget today what you and I combined will ever know about these engines.
Let us know how your search turns out and welcome to the Bolt.
