I run Delo 15W-40. I kinda think the oil consumption may be due to a bad valve guide on the cylinder that loses air if the air loss is not due to a burnt valve. Then again, I've read on this forum that some say even 1 qt/1000 mi is within "normal" for the m103. So, I don't feel too bad about 1qt/3000 miles. I have no leaks.