Originally Posted by fingerlickin'
Judging by the look of those ribs, I would say you have a meat quality issue. IMO with the thickness of those I would think they would be done in 2-3hrs max. Listen to Phubar and try the bend test next time. It's very hard to get an accurate temp measurement on ribs, that's why most use the bend test or toothpick test instead. You may consider skipping the foil all together next time or adjust the method to something like 2 hrs on grate, 1/2 hr in foil and 1/2 hr or till done on grate to firm up. Good luck!
Meat quality and the brining would be my guess. I always take a peek at about the middle of the cook and correct my timing based on how things look.
I also do not foil on the grill, only if I have time to let them set after cooking.