I have a Ford V-10 truck. All the Triton motors are known to have this issue 4.6 5.4 and 6.8 liters. Napa has this fix
Dorman 42025 HELP! Master Cylinder Head Repair Kit : Amazon.com : Automotive
Which I found in-store. I have about 15K miles on my truck with no issues after this repair. If it happens again there are other helicoil insert repair kits available. They usually require removal of the head.