I have 1997, BMW 328i auto with 147,000. I have used 15W-40 dino (Rotella T) since 25,000 miles with no consumption. Oil change interval at 3,000 - 3,500.
I've just noticed a slight oil consumption, 1/2 qt per 3000 miles plus a minor leak at rear of motor, just above the round cross member/bar...