I'm not familiar with the 55, but the 48-53 1 tons use same brakes, and in fact same rear axle altogether, for the singe and dual wheel trucks with one exception of wheel stud length.

If you have single type wheels up front it was probably singe wheel truck from the start, unless someone changed hubs along the way.

You probably need 16" or larger wheels to fit over rear brakes, and as mentioned most any older 8 lug wheel (non metric bolt pattern) will be the same old 6.5" bolt circle and may fit.

•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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