For this procedure it will be necessary to acquire a new set of 11 mm cylinder head bolts. Start with the process of clearing out pressure on the fuel system, next step is the removal of the cable on the negative terminal of the battery and the draining of the cooling system as well. The intake manifold must be either unbolted or sometimes pulled off and for 5.3L and 6.2L engines, fuel rail(s) also to be disconnected from cylinder head(s). Remove the cylinder head bolts, exhaust manifold(s) and untighten but do not remove the exhaust pipe(s) from the exhaust manifold(s), then remove the valve cover(s) and the rocker arms and pushrods and lay them in order to assemble it back. Subsequently, take out the coolant air bleed pipe aside, the alternator with its bracket and lower the ground strap from the back of the left cylinder head. As for the right cylinder head, on 6.0L models, it is necessary to remove the dipstick tube and to disconnect the ground cables at the front of the cylinder head. Back off the head bolts in a counter-clockwise direction, one quarter turn at a time, in the reverse order that they have been tightened unbolt until they are easily removable, observe different length and sizes of bolts needed for replacement with the new ones. If the head has warped set it on the blocks of wood or if you need to remove it fully, then use pry bar or long screwdriver and lift it gently off the engine and store it properly in order not to spoil gasket sealing surfaces. As for the cylinder heads mating surfaces, they should be absolutely free of any contaminants, thus making use of gasket removal solvents and a gasket scraper in order to remove the carbon and the residual gasket material. It is recommended that the block and head mating surfaces be inspected for any sign of damage, and if there are slight imperfections then take the same emery cloth while in cases of a lot of damages, it is recommended that one takes a machine. Use a tap to chase the threads in the head bolt holes and if you do not have access to a tap then clean it with brake cleaner and compressed air as the last resort. Install the new gaskets on top of those dowels in the block, then put the heads on the block gently without moving the gaskets and put a medium strength thread locking compound on the threads of the new 8mm head bolts. Use the new 11 mm head bolts and tighten them only with your hand to a light torque and then use the recommended pattern to tighten the bolts in four passages to reach the required torque. Replace coolant pipe with new gaskets and tighten bolt and to complete the process reversed manner of its removal. Last of all pour coolant, replace the oil and filter, switch on the engine and look for normal signs and any signs of leakage.