sealant is only required to fill in voids, which would be the result of damage to the block surface or a distorted pan (usually the pan). the gaskets, whether cork or synthetic, are designed to be compressed slightly, but not crushed into place (which usually comes from over tightening) i've had good luck with two oil pans using the following method: - use a piece of 1/4" aluminum flat bar clamped in a vice as an anvil to get up inside the flange, then go around the perimeter tapping out all the distortions to get the gasket surface dead flat. it's about patience, not force - the sheet metal deforms very easy so you can use a small hammer. - put in all the fasteners finger tight before torquing any, then go around and tighten them evenly, a little at a time until you get them all to spec (which is not very tight). - re torque after a day or so, as the gaskets squish a bit. use the same method of going around the pan a little at a time. the key is not to over tighten, as this will dimple the pan and then it will leak for sure. and if it does leak, you can bet you over tightened...