From what I've been able to ascertain, all 3800s of the era came with a plate stating 8800 lb gvw. However, to be capable of carrying that weight, they did indeed have to be outfitted with the 7.00X18 8-ply duals and 2-stage, 8 leaf and auxillary springs. This is explained in the reprint of the Chevrolet Truck Shop Manual 1948-51 with '52 suppliment. The note states " These GVW ratings are reduced per above table when tires of a lesser capacity are used."