In time the GMC cylinder head gasket sets will be required to be used on most trucks. This is the material that seals the contact area between the cylinder head and the engine block itself. Not only is this gasket responsible for the sealing of each combustion chamber, but also the water and oil galleys between these two engine components. The most common reason for the need to replace the cylinder head gasket set on a GMC truck is because of a break in the cylinder head gasket material between a water galley and one of the combustion chambers. This condition will be noticeable in two ways. Water can be leaking into the crank case causing the oil to foam up. The exhaust can also be billowing white smoke when the engine is running. The worst of the two conditions of a blown cylinder head gasket set is the leaking of coolant into the crank case. This will scar the bearings in the engine in a short period of time. If this problem is not addressed immediately you will be using the GMC cylinder head gasket set when the engine is being rebuilt instead of just fixing the leak. When the repair job on your GMC truck is being done, the inspection of the cylinder head and block areas where the leak occurred is critical. If there is any pitting or unevenness in this area or any other part of the contact area, then the surfaces will need to be sent to a machine shop so a flat surface can be again be achieved for your GMC engine. If this is not done another cylinder head gasket set will be needed in the near future because the one on the engine will blow out again.