I posted this in the 'Big Bolts' section, but wonder if you guys could help with the engine ID.

hi folks, this weekend i got my hands on a big GMC. unfortunatly i dont know anything about it.
there is an oval badge on each side of the hood that says '3 TON'. I know it was made in Canada
there are two badges attached to the door pillar that say:

Model 9773
serial 0977312337
Engine G28643
Body Serial 577
Trim 394
Paint FC94
the max weight rating is 16000 lbs

I dont even know what year it is, but its the same body style as my '48 (AD) The gas tank is behind the seat inside the cab, and the front glass is two pieces.

I pulled the engine out and was even more confused to find that the only casting number behind the starter motor was '5'

there is no casting # on the plate behind the distributer, it is blank, and appers to never have had a number their (does not look like it was tampered with)

i did find a number cast into the block below the exhaust manifold that reads '6107328'
does anyone know what this engine is?
or for that matter anything about the truck?


1948 3600 thriftmaster