yeah, interesting question. I've often wondered myself, as I've done work on a vehicle that had a "no-retorque" head gasket, and I wondered what the difference was.

then there are some vehicles that recommend replacing the head bolts, and, in fact, they come as part of the head set. others don't. I don't know, maybe newer vehicles use a different head gasket design in combination with stretch bolts? pure speculation...

but yeah, I've also heard 500 mile retorque recommendation on this engine.

msg - '87 xtracab