98vortec

hi all. this past weekend i replaced the head gasket on the left side of my 98' 1500 with the the 5.7. to what we thought was the head gasket actually wasnt and the cylnder head looked good too. so we reassembled with all new gaskets and fired it up. it was still making lots of white smoke really bad that smelled like coolant. the truck heated up really quick and almost overheated on my 1 mile ride back from our shop. we had came to the conclusion that the block may be cracked. i remembered a couple weeks before that coolant was leaking out around the oil cooler lines on the radiator in small amounts. is there any way that the coolant and water could be making its way into the oil cooler and mixing with the oil?

thanks,
Derek