Originally Posted by pitzel
Esso XD-3 0W-30 since 2004. 58k since my last oil change, and roughly 100k since I began the regime (first run was interrupted by the notorious GM lower intake manifold coolant leaks!). When the oil pan was off at 45k or so, no sludge, only very minor varnishing. Put the drained oil back in (I paid a lot of attention to ensuring it was removed cleanly) and kept running it.
So no coolant leaked into your oil, at point of interruption?