Hinting at its roots in the previous generation Thunderbird that it evolved from, the new model retained a similar grille design with dual headlights and a 113.2 inches (2,875 mm) wheelbase.
As before, the new Thunderbird continued to be offered in hardtop, convertible, and Landau versions. The 300 horsepower (220 kW) 390 cu in (6.4 L) FE V8 continued as the standard engine for the Thunderbird. It was paired with a 3-speed automatic transmission. For 1965, sequential turn signals were added, flashing the individual segments of the broad, horizontal tail lights in sequences from inside to outside to indicate a turn. Also new for 1965 were standard front disc brakes, and doubled sided keys.
Even though it was the last year of the generation, 1966 saw a stylistic revision for the Thunderbird highlighted by a new egg-crate style grille with a large Thunderbird emblem at its center and a new rear fascia with the brake lights restyled to appear as one unit. Engine choices were also revised for 1966. The standard 390 cu in (6.4 L) V8 equipped with a single four-barrel carburetor produced 315 horsepower (235 kW). Newly optional and taking the top position for performance was a 345 horsepower (257 kW) 428 cu in (7.0 L) FE V8. The 428 cost only $86 over the base engine, and was a popular option.