I have been running Mobile 1 15W-50 for a couple of years and have not had a problem. Napa ran a sale last spring for 5.99 qt and I bought 8. Today I needed to do the oil thing and found a 5 qt jug at Wallmart for about 27$ Same grade full synthetic with wear protection. I still had the 1/10 of a qt left in one of the old quarts so I used it. I then noticed the old qt oil was darker than the new jug oil. I went on line and Mobile only list one 15-50 grade. The jug was labeled API SN and the Qt was labled API S N M/CF. Anyone noticed different colors of the same weight of oil and know why the jug would be labeled different than the Qt? I like the lighter color because it looks newer.
From their website:
Mobil 1 15W-50 synthetic oil meets or exceeds the requirements of:
API SN, SM, SL, SJ
ACEA A3/B3
Mobil 1 15W-50 is of the following quality level:
API CF
