Thx for responding so quickly. i have already replaced the lifters and have put the engine back together and everything. i also changed spark plugs, wires, coils, and fuel injectors, and still i have a misfire on #4 cylinder. So i removed the valve cover and cranked the engine and thats the only cylinder that is not working. So you think its the vlom........I sure hope so......thx for helping me out. ill see about changing it today or tomorrow. my wife is so aggravated right now with this truck lol.