A subject certainly worth knowing about are cylinder block cracks on the Cadillac 4.6L DOHC engine. You may never see one of these cracks unless you painstakingly look for it or it bites you on a warranty. However, it becomes obvious almost immediately if you need to resurface the block deck.
The problem is cracking of the aluminum block casting around the cast iron liner (Figure 1). Knowing that this possibility exists, it is strongly recommeded that you take the time to make a close examination of the deck prior to doing any machining at all and before you then spend numerous hours installing cylinder head bolt repairs.