Preheat the oven to 325 degrees.
Mix the ingredients together for the dry rub then season the ribs on both sides, using all or most of the dry rub.
Place the ribs on a baking sheet lined with foil, then cover the sheet pan with foil on top.
Bake the ribs in the oven for 2 1/2 to 3 hours until tender. Remove from the oven and set aside until ready to grill.
To make sauce, heat the oil in a saucepan over medium heat.
Add the garlic and cook for 30 seconds, being careful not to brown the garlic.
Slowly pour in the root beer liquor and let reduce for 2 minutes, then add in the rest of the sauce ingredients and stir.
Cook the sauce on low heat, simmering, for 30-40 minutes until thickened. The sauce will also thicken more as it cools.
Place the ribs on a medium grill (about 400 degrees) for 5 minutes on each side until warmed through.
Flip the ribs over so the bottom side is up and baste the ribs with a good amount of sauce then close the lid and cook for 5 minutes
Turn the ribs over so the top of the ribs are up and baste with the sauce then close the lid and cook for another 5 minutes.
Baste the ribs with another layer of sauce before taking them off the grill.
Oven the ribs have cooled slightly, cut the racks into sections of three to four ribs and serve with extra sauce on the side.