I switched to mobil one good news/bad news

[daverdla]

I don't want to start an oil war but....
I switched to mobil 1 diesel/suv oil, 15 30w I think, 3000 miles ago. Two good things - less noisy and less oil consumption. I've put 12,000 miles on since last march, right now the cars got around 140k miles. I had the oil change with dino for the first 3000 and 6000 miles changes and it dropped about a half a quart or so after 1500 miles. Although mildly inconvenient, not really a concern. Now I've driven about 3000 miles with no noticable oil consumption but I've noticed a little bit of blue smoke when I start up first thing in the morning. I realized that it takes very little oil to make the blue smoke but it is annoying. The car had new valve guides shortly before I bought it. Could it be valve guides? I plan to give it some time and see how it goes.