I'm not concerned about cold weather startup. I bought this Civic in 89 and consistently used those heavyweights of GTX for the first 90,000 miles. Then someone told me it was a bad idea, and I switched to xW30. I've got 120,000 on it now, and it seems to use some oil, maybe a quart every 6-800 miles, but doesn't seem to burn it. I don't see any smoke. And there are no leaks. I can't figure out where it goes. I'm just wondering if I jacked something up in the engine from all those years of using the heavier weight oil? What could be happening to the oil?