Preheat Traeger Grill to 225F. After you set the temperature, close the lid and let it heat for 15 minutes.
Prepare the tri tip by trimming any fat or silver skin left. Drizzle the roast on both sides with vegetable oil. Season the beef on both sides with the rub.
After the pellet grill has preheated for 15 minutes, set it directly on the grill grates and close the lid.
Smoke the tri tip for approximately 1 hour and 45 minutes, or until the internal temperature reaches 135F for a Medium beef.
Remove the tri-tip from the pellet grill and cover with foil. Allow it to rest for 15 minutes before slicing. This is important.
Slice and serve. Be sure to follow slicing guidelines.