Make sure they are cracks and not casting marks. Seen this many times where people think they are cracked, when it is actually just part of the casting in the aluminum.
I wish, these are the real deal. Truck was stolen once and they tried to remove either the motor and/or trans, they had left the bolts loose he didn't realize it until it started to come apart. I told him he needed to check it thoroughly but he just got in an continued to drive it that way.