RPO-273 is the optional 15" tire on USA Chevrolet trucks
There are no RPO numbers (that I can find) for optional tires listed (in two places) in the 1954 Canadian Truck Sales Data Book.
1300 (except 1316, Suburban) series Optional Tire Equipment
6.00 x 16 passenger [grade] tire BASE TIRE
6.50 x 16 passenger [grade] tire
6.50 x 16 truck tire
7.00 x 15 truck tire (5 times the price of the 6.50 x 16 tire) - this is listed as the only Optional Tire for Suburban
