The GMC Terrain 1.6d 137hp (2017 - 2020) produces 137bhp and 325Nm in standard form. Our Stage 1 ECU tuning file raises output to 165bhp and 380Nm, a gain of 28bhp and 55Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.