2005 CADILLAC ESCALADE Engine And Engine Coolingexhaust System Problems

I HAVE A 2005 CADILLAC ESCALADE 6.0L ENGINE, WITH 88,000 MILES ON IT. I HAD A TICKING SOUND INVESTIGATED BY A LOCAL MECHANIC AND HE FOUND 3 EXHAUST MANIFOLD BOLTS, TWO ON ONE SIDE AND ONE ON THE OTHER, HAD SPONTANEOUSLY BROKEN. HE INDICATED BEFORE HE LIFTED THE HOOD THAT WAS THE PROBLEM BECAUSE "THAT WAS A COMMON PROBLEM WITH THE 6.0L ENGINE". I CHECKED WITH CADILLAC OWNERS GROUP AND EDMUNDS CAR SPACE AND READILY FOUND SEVERAL SIMILAR COMPLAINTS WITH THE 6.0L GM ENGINE. THIS SHOULD NEVER HAPPEN AND COULD LEAD TO AN ENGINE COMPARTMENT FIRE AND/OR THE LEAKAGE OF EXHAUST GASES INTO THE SAME. I HAD ALL OF THE MANIFOLD BOLTS REPLACED. THEY DIDN'T APPEAR TO BE EXCESSIVELY CORRODED, BUT RATHER, THE HEADS OF THE 3 FAILED BOLTS APPEAR TO HAVE JUST POPPED OFF. I HAVE THE BOLTS THAT WERE REMOVED AND REPLACED. THIS PROBLEM IS SOMEWHAT INSIDIOUS BECAUSE...