[LEWISMATKIN]

azken, an I-1000 was a 48-state GMC equipped with a chev. inline 6. As to the smoke problem, if the oil was overfull before the change, did it smell like gasoline, having a very thin feel to it, or when draining the oil, it seemed very thin coming out of the oil pan? If so, you may have a leaking fuel pump pouring fuel into the oil pan. that can cause oil to be sucked into the pcv system. Another cause could be the carberator either flooding or the choke plate stuck almost closed. In any case, try not to run the engine very much until the problem is solved, before the cylinders get washed down with this problem. Also, if the truck is quipped with a power-flo (chev. powerglide) a/t, the vacuum modulator diaphram could be ruptured and the engine sucking the fluid out of the transmission. I hope this is of some help in the resolution of this problem.