My husband LOVES ribs. But, he's a bit of a connoisseur -- he loves fall-off-the-bone ribs. And, when I want to achieve a certain quality, I start with America's Test Kitchen -- in this case, their Master of the Grill recipe book (I highly recommend). This recipe makes that happen. But. . . I want to try out different spice mixes, and I'd like to tackle something more wet, so any suggestions are welcome!
Dissolve sugar and salt in 4 quarts of cold water in large container. Submerge racks in brine, cover, and refrigerate for 1 hour. Remove pork from brine and pat dry with paper towels. Let ribs sit at room temperature for 1 hour.
Just before grilling, soak wood chips in water for 15 minutes, then drain. Carefully wrap in aluminum foil (double regular aluminum, or single sheet of heave duty foil), then place 2 slits in the top to vent the smoke.
Remove cooking grate and place wood chip packet directly on primary burner. Set cooking grate in place, turn all burners to high, cover, and heat grill until hot and wood chips are smoking, about 15 minutes. Turn primary burner to low and turn off other burners. (Adjust the primary burner up, as needed, to maintain a temp of 300* - 325*. Crack the grill open, if needed, to pull the temp down.
Clean and oil cooking grate. Place ribs meat side down on cooler side of grill. Cover and cook until ribs are deep red and smoky, about 2 hours, flipping and rotating racks halfway through grilling. During final 20 minutes of grilling, adjust oven rack to lower-middle position and heat oven to 325*.
Transfer ribs to wire rack set in rimmed baking sheet. Cover tightly with foil and cook in oven until tender, 1 - 2 hours.
Remove ribs from oven, loosen foil to release steam, and let rest for 30 minutes. Slice ribs between bones and serve.