The Stovebolt Site Forums The Parking Lot Big Bolts 1951 GMC water tanker, help identifying

Nope, not a 1 1/2 ton. A 1 1/2 ton GMC is a 300 series. 2 ton 350 series, 2 1/2 ton 400 series, 3 ton 450 series, & 3 1/2 ton 470 series. You have a 450 series 3 ton. GMC rated gvw on that truck is 19500 lbs. Look for the ID plate in the driver door jamb, & the "GMC Parts Identification" plate on the back of the glove box lid. It will be on both these plates.