standard on the Imperial Crown . 1955–1983: A separate brand 1955-1975 Chrysler Corporation advised state licensing bureaus that beginning in 1955, the Imperial was to be registered as a separate make. It was an attempt to compete directly with GM's Cadillac and Ford's Lincoln distinct luxury-focused marques. Frequently and erroneously referred to as the "Chrysler Imperial", these cars had no "Chrysler" badging anywhere on them until 1971 (although it was removed by 1974), and were a separate distinct marque, just as Lincoln and Cadillac were for Ford and GM. Starting with the 1974 Imperial models, the "Chrysler" badging was again removed from its car body, with only the "Imperial" nameplate appearing. In April 1955 Chrysler and Philco announced the development and production of the world's first all-transistor car radio. The radio, Mopar model 914HR, was a $150.00 "option", or equal to $ today on 1956 Imperial automobile models. Philco began manufacturing the all-transistor car radio for Chrysler in the fall of 1955 at its Sandusky, Ohio plant. With the new "Imperial" make, Chrysler Corporation's intention was to create an individual line of luxury cars, above and distinct from Chrysler branded vehicles. This marketing strategy suffered because the cars were rarely (if ever) sold in stand-alone Imperial showrooms. Cadillac and Lincoln did a much better job of separating their luxury marques from the lower priced cars that they sold. Imperial was instead offered at the Chrysler dealer network alongside Chrysler's offerings, and the marque was almost universally known as "Chrysler Imperial" in the public's mind for this reason, despite the fact that all existing dealerships did indeed carry separate "Imperial" dealership signs distinct from Chrysler. The Imperial automobiles continued to be retailed through Chrysler dealerships. A distinct marketing channel was not established; thus, the Imperial nameplate failed to separate itself from the other Chrysler models and become a stand-alone marque. Beginning in 1967, the Imperial Division, offering three ranges (Custom, Crown, and LeBaron), retreated from their separate body-on-frame construction and their unique body on a 129.5-inch wheelbase. From that time, Imperials used the Chrysler body. It was fitted with unique styling, and through 1973, very long hoods which accounted for the three-inch-longer (127 vs. 124") wheelbase as compared to other Chrysler sedans. They continued to use their unique front suspension with torsion bars longer than all other Chrysler products and a rubber-isolated subframe crossmember containing the torsion bar anchors, as well