Originally Posted By: jstutz
My father in law uses Rotella 15w40 in everything he ownes and one of them is a Buick with the 3.1, a 4 cylinder cavalier, and two pickup trucks. He lives is PA and runs it all year long. I dont believe this is a best practice because of the cold winters but he has had a lot of vehicles through the years and i dont believe any of them failed due to an oil related issue. Personally i would use it and just be aware that on cooler mornings the oil will be a little thicker. I have seen so many people run Rotella in everything and not have issues. If i was buying it i would choose a 5w30 or something but if i had it and conditions were mild, i would use the hdeo and not be worried about it.
Same here, Up in Pa, we used 15w40 Pennzoil Longlife in everything, because we bought it bulk for trucking. Although we bought it to use in Tri-axle trucks, we used it In the cars, Dodge Caravan, pickup trucks, atvs, motorcycles, lawnmowers, whatever and we had no problems. It went way down past 0 in the mountains and we used it all winter long without problems. thats why it cracks me up that people think 10w30 is to thick below 32. Use it and it will actually keep your engine cleaner than any gasoline speced oil.