t3's are tylenol 3,but i dont know how to explain to you the differance between the two.just that oxy contins generally have a greater amount of oxycodone in it but in slow release.that is why people chew and crank oxycontins.i believe that oxycondone is a more refined stage of the opiate then codeine.but hey i have not the education to explain it,so i suggest you research it,i think one of the above posts said it right.