Take the roast out of the refrigerator 45 minutes prior to cooking.
Place it on a platter or in a glass baking dish with the fat side up.
Score the fat about an inch apart with a sharp knife.
Turn the plate 90 degrees and score again to form a hatch pattern. Do not cut into the flesh.
In a small bowl, mix together all of dry rub ingredients.
Season the meat all over with the rub, pressing it into the roast with your hands.
Fill the hopper of the Traeger grill with wood pellets, enough to last for at least 2 hours according to the package directions.
Line the drip tray with aluminum foil for easier cleanup.
Turn the smoker on with the top open until a flame is established, approximately 5 minutes.
Close the top and adjust the temperature to 225˚F.
Allow the grill to heat up for 10 to 15 minutes.
Place the tri-tip, fat side up, on the lower smoker rack.
Insert the attached probe thermometer in the fatter end of the roast.
Close the top. Smoke for approximately 2 hours for medium rare.
You can check the meat at 60 minutes.
You are looking for an internal temperature of between 130˚F to 135˚F.
A well done roast might not be as tender.
Remove the roast to a clean cutting board and tent loosely with foil for 20 minutes to allow the juices to be reabsorbed.
Slice the roast thinly against the grain and serve with your favorite side dishes.