The Factory Service Manual (Section 6B) advises to pull the driver's side drain plug, and also the knock sensor (right side) to fully drain the coolant from the system. I'm accustomed to this on both LT1 and LS engines; it's the requisite coolant shower when performing a DIY coolant flush and properly draining the block. And those plugs really gush, like 50%+ more coolant comes out versus just draining the radiator.

On the 3.4, I got what looks like ~2 ish gallons when I drained the radiator and also changed upper/lower hoses for new ones. The drain plug next to the oil filter on the driver's side is easily accessible, as is the knock sensor on the right side. Golden. The cooling system was supposedly FULL when I started this project. Radiator was filled to the top and the coolant bottle to minimum @ cold.

I drained the radiator first and changed out the hoses. When I undid the drain plugs, nothing came out. It doesn't appear there's water inside of there--at all. Or that there ever was.

If coolant wasn't circulating around the cylinder jackets, I'd think the engine would have been in serious trouble. I put about 50 miles on the car last weekend, and it's done a couple of idle cycles where I verified it reaches operating temp, gets warm, and then activates the fans at ~225 degrees and cools things right back down.

What am I missing?