been thinking about switching my 140,000 mile '94 toyota 4runner to it. I bought the truck with 115K, previous owner used typical dino 10-30s like Penzwax. I've run mobil 1 10w-30 in since. it's got the 3.0 V6 and it doesn't smoke. I live in south Florida and it gets very hot in the summer and even hot in the winter. My 4runner is a very modified off-roader and daily driver. 35" MT tires, Dana 44 front axle, metal bumpers, etc. I daily drive it in tampa's traffic and wheel it hard on the weekends and it sees a good amount of "highway" driving.. i have 5.29 gears so it revs decent at 70; 3grand. Reason I've been thinking about switching is A-Cost.. I'm tired of paying mobil 1 prices. 2- I researched API ratings and the diesel oils seem to meet higher standards. and I heard bad things about the new SM oil rating.