All I will say is that this forum doesn't seem to be filled with questions concerning blown head gasket issues. Cracked heads yes, blown head gaskets? No.
Folks acquire these trucks with old engines which have been ridden hard put away wet. We get all kinds of questions about all kinds of issues. Lacking from that list of questions is "what do I do about the warped head, or why do I keep blowing head gaskets?"
Given this less than scientific observation, I wouldn't worry about head gasket failure on these tractor engines. It does not seem to be inherent to these engines.
The GM engineers seem to have added enough margin of error in their head/block design, effectively eliminating blown head gasket issues.
