1.  Whisk together 4 cups of cold milk with the two packages of pudding.  Whisk for 2 minutes, then set in the refrigerator for about 3 minutes to firm up.
2.  Layer the bottom of a 9 x 13 cake pan with Oreos.  Break some into smaller pieces to fill in along the edges.  Spread half of the cheesecake pudding evenly over the Oreo layer.  Cover the layer of pudding with another layer of Oreos.  Spread the remaining pudding, then the whole container of Cool Whip.  Break some of the remaining Oreos over the top and drizzle on the chocolate syrup.  Cover and refrigerate for at least 4 hours before serving to allow the Oreos to soften.