The Series 60 was Cadillac's mid-priced entry in the luxury vehicle market when it appeared in 1936. The Series 60 was the brainchild of new Cadillac manager, Nicholas Dreystadt. Debuting in 1936, it filled a gaping price gap between the LaSalles and series 70 models. Initially it rode on a 121.0 in (3,073 mm) wheelbase and shared the B Body with with cars from LaSalle, Buick and Oldsmobile.
The exterior featured a new Harley Earl-designed look with a tall, slender grille and split vee-shaped windshield. This body used Fisher Body's new Turret Top one-piece roof and Bendix dual-servo brakes. "Knee-action" independent suspension, first introduced by Cadillac in 1934, was a welcome novelty for the mid-price market at the time.
Under the hood was the new (less expensive) Monobloc V8 5.3 l (322 cu in) engine produced 125 hp (93 kW), just 10 less than that in the larger Cadillacs. The Series 60 immediately became the company's best-selling model, making up half of all Cadillacs sold the first year.
The next year, displacement on all Monobloc Cadillacs was 346 cu in (5.7 L). This new engine produced 135 hp (101 kW), more than all V8 Cadillacs of just a few years earlier.
For 1938, the Harley Earl-Bill Mitchell designed Sixty Special was added between Cadillac's lowest-priced line of cars, the "Series 60", and the "Senior" large-bodied Cadillacs. Although all first-generation 60 Specials were built at the Fleetwood Plant, the 60 Special was marketed as a Fisher Body car in 1938 and 1939.
The new four-door sedan, designed to look like a convertible sedan, showcased trend-setting features including a completely integrated, coupe-like trunk (which launched "three-box" sedan styling); no running boards (which all makes soon followed); two-piece, convertible-style doors (Bill Mitchell called the '38 60 Special "the first hardtop"); a "four-window" canopy with more glass area than any Cadillac before; a steeply-raked windshield and four front-hinged doors. Contrary to what was then the trend in luxury automobiles, the new Sixty Special was intended as an owner-driven car, rather than a chauffeur-driven one
The Series 60 was superseded by the Series 61 after 1938.