The E Series of Studebaker trucks can have two definitions. It originally meant 1955-model Studebaker Corporation trucks, sold in half-ton, 3/4-ton, and 1-, 1.5-, and 2-ton capacities. Later models were classified by Studebaker as follows: 1956: 2E series; 1957-58: 3E series; 1959: 4E series; 1960: 5E series; 1961: 6E series; 1962: 7E series; and 1963-64: 8E series. Given these model-year designations, "E series" has come to mean all Studebaker trucks built between 1955 and the end of all vehicle production in the US in December 1963. Within each tonnage rating, these trucks were all fairly similar, since Studebaker was in dire financial straits during this entire period and invested virtually nothing to update its truck division products. For the 1956 and 1957-58 models, all Studebaker trucks were called Transtar. A new massive fiberglass grille appeared on the 1957-58 3E models, and was the last significant styling change made to these trucks.

For the 1958 and 59 model years, a stripped-down, low-cost Studebaker truck, called the Scotsman, was produced in addition to the Transtars, in 1/2 and 3/4-ton ratings. To save money, it used a modified version of the 1949-53 grille and was spartan in almost every way. For unknown reasons, the Transtar name was dropped from the Studebaker truck line in 1959, though it reappeared in 1960 on the 1-, 1.5-, and 2-ton models. A new Champ truck replaced the comparable Transtars in 1960, and was available in 1/2-ton and 3/4-ton models. Its styling was based on the 1959-60 Studebaker Lark passenger car.

The 1/2, 3/4, and 1-ton trucks were generally available with both 6-cylinder and V8 engines (no 6-cyl in 1-tons after 1960). Larger trucks came with V8s only. Beginning with the 1962 7E models, a Detroit diesel engine was also available in those of 1-ton or above capacity, and air brakes could be had on 2-ton models. A "96BBC" (meaning 96 inches from bumper to back of cab) was available in both gasoline- and diesel-powered models beginning in 1962. The short cab length was achieved by deleting the fiberglass grille, flattening the front of the hood, and applying a very distinctive flat nose below the hood. This model was produced in response to some state laws that restricted the overall length of tractor trailers, and thus permitted the use of longer trailers.

Four-wheel drive was available on 1/2 and 3/4-ton models beginning in 1957. Studebaker did not make the 4WD equipment themselves, but (in common with Chevrolet and GMC at the time) purchased the hardware from NAPCO (Northwestern Auto Parts Company).

The most distinctive characteristic of Studebaker E-series trucks is the cab, which remained unchanged throughout its production run. With only two changes (a one-piece windshield in 1954 and a larger rear window in 1955), it was essentially the same cab as was introduced on the 2R series in mid-1948 as a 1949 model.