The need to replace the Toyota valve cover gaskets and seals has been reduced since the introduction of the hydraulic lifters in the valve train. This component has made the need for the periodical adjusting of the valves no longer required for the engine to operate correctly. Today the leading reason for the Toyota valve cover gaskets to be replaced today is to stop an oil leak that is making a mess on the rest of the engine. This is because the valve cover gasket and grommets are on the upper portion of the Toyota engine block, and any failure in their sealing ability to stop the oil from flowing out will cause all the components below it to be covered with the leaking oil. The replacement of the valve cover gaskets is a very easy and straight forward procedure. The most difficult part of the repair process is gaining access to the valve cover and the cleaning of the old gasket material from both the bottom of the cover and the top of the cylinder head. Most Toyota owners can complete this repair procedure in less than an afternoon. One precaution that should be taken when the valve cover gasket and seals are being replaced is to make sure all of the old gasket material is removed from the block. This has to include the small amount of material that will fall into the valve head itself. If this is not done and the Toyota engine is sealed up, these small contaminants will end up in the oil galleys and could hinder the flow of the oil in the engine. The replacing of the value cover gasket and seals is not complicated just time consuming if it is to be completed correctly.