My wife made me get off the computer before I could finish my previous note, so here I am again.
Can't help you much with I-65 places. Haven't traveled that road much.
But if you take I-75 here are a couple of suggestions:
Bradley's Barbecue, Sweetwater, TN. About halfway between Knoxville and Chattanooga, about a mile east of I-75 on the road into Sweetwater (you'll see it on one of those where-to-eat signs at the freeway exit). Best 'cue I've had in Tennessee, and, yes, that counts a bunch of places in Memphis. We never travel I-75 anywhere near meal time without stopping.
In Kennesaw, GA (an Atlanta suburb), there's Big Shanty Smokehouse. Everythings's good, but it's the ribs that draw raves. (Exit 273, Wade Green Road, then about a mile west to 3393 Cherokee St., which is the same as Wade Green; the name changes along the way.)
Between Atlanta and Columbus, just south of I-75 in Newnan (exit 47), there's Sprayberry's, which is a legendary spot. I ate my first 'cue at the original location (this one is relatively new) almost 70 years ago, and have had some fine meals there since. I fear success has gone to their their head, though. I don't think it is even in the top 50 percent of Georgia pits now. A lot of people love it, however, so you might take a chance if you're there at mealtime.