Preheat pellet grill to 250 degrees F.
Combine rub ingredients and apply evenly to the entire surface of the chuck roast.
Place roast on cooking grate and cook for 3 to 4 hours or until the meat reached an internal temperature of 160 to 165 degrees F.
Wrap the roast in aluminum foil, adding 1/2 cup of beef broth heated to near boiling. Place the roast back on the pellet grill and increase the temperature to 300 degrees F.
Continue cooking until the meat reaches an internal temperature of 200 degrees F., about 2 to 3 hours depending on your grill. Set aside to rest for ten minutes.
Unwrap and shred beef, removing any bits of fat or connective tissue. Keep warm in a pot with remaining beef broth. Serve and enjoy.