[factorystock]

'64 C 20 with 17" heavy duty 3 piece rims, not the 15" 3 piece heavy duty rim as seen on the '64 GMC 1500 above. The 15" tire was ok for 1/2 tons, but a serious miscalculation by GM having them available on 3/4 tons up to early '65. The new for '65 16" 2 piece wheel became the wheel of choice for 3/4 tons the next several years till the 16.5" became available.