1995 BMW 325i, 176k, bought almost 2 years ago @ 158k. PO used 20w-50 Valvoline bulk conventional since purchasing it as a lease return in 1998. Have all records, PO was a good one, but the engine looked just slightly varnished inside the filler cap. Ran 3 OCIs at about 6k using T6 twice then DELO 5w-40 syn, and didn't burn but a drop.
So I figured I'd drop it down to a 30wt (via blending) and see how it behaves. Too early to tell for sure but so far great! No burning, (yet anyway) averaging 27mpg, (up from 26) 80/20 hwy/city, but about 30-40% of the "hwy" miles are thick traffic East Bay commuting miles.