In a bowl, whisk together the peach jam, Dijon mustard, orange juice, salt and pepper.
Preheat your grill to high heat, about 475° to 500°F(250° to 260°C).
Coat pork with olive oil and season with salt and pepper. Sear on both sides for 4 minutes without moving.
Lower heat to medium-high, about 375°- 425°F(190° to 220°C). Brush with peach glaze. Continue cooking for 4 more minutes per side, brushing with peach glaze when you flip.
Total cook time will depend greatly on the size and thickness of your tenderloin so use an instant-read meat thermometer to check the temperature. Remove when it reaches 130°-140° F(55° to 60°C) internal temperature, depending on your preference.
Let rest for 10 minutes. Slice the tenderloin and arrange on a serving platter. Drizzle with the peach glaze before serving.