These preformed 5/16‑inch OE‑steel transmission‑cooler lines replace the original lines on 1987– F100 and F150 2WD trucks with the heavy‑duty cooling C6 transmission, following factory routing from the transmission to the radiator. The ‑piece set is CNC‑manufactured using patterns from original lines and includes the correct fittings, flares, and protective wrap to ensure a precise and dependable cooling‑system performance.