I just looked in the GMC model 400-980 1947-53 parts book.
A DW455-37 truck had an Eaton SR 22M rear axle, no optional axles listed. Wheelbase of 197”.
Looks like it would also have a Spicer 5531B auxiliary transmission behind a Clark 204 VO

I presume tandem axles could be added aftermarket when the truck was new, or perhaps special ordered?
Seems to me if you needed tandem axle you’d be a lot better off with more engine than the little old 3-71.

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
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