Preheat your grill to 275°F (135°C) using the indirect heat method. This means that you'll only light half the burners and place the ribs on the side without the lit burners.
In a small bowl, combine the garlic powder, onion powder, smoked paprika, brown sugar, salt, black pepper, and cayenne pepper to make a dry rub.
Rub the dry rub all over the ribs, making sure to cover every inch
Place the ribs on the grill, bone side down, and close the lid. Cook for 2 hours.
After 2 hours, mix together the BBQ sauce and apple cider vinegar in a small bowl.
Brush the ribs with the sauce mixture and cook for an additional 30 minutes.
Brush the ribs with more sauce and cook for another 15-30 minutes, or until the meat is tender and falling off the bone
Remove from the grill and let rest for a few minutes before slicing and serving.