quote:As long as it's an SL rated oil, and you keep the drain interval reasonable, you shouldn't have any problems.
Originally posted by huxley7: Owners manual says to use 5w-30 or 10w-30. I have a case of 10w-40 will that hurt the 3.0 liter engine?
quote:The age of the car is irrelevant. I recommended an SL oil to ensure that the oil is not one of the older 10w40 grades that is made with Group I base oil and loaded with VI improvers. These older 10w40 oils were notorious for sludge and camshaft wear problems.
Originally posted by pruntyc: As the SL rating is pretty new, I don't believe it would need to have it, in a 1991 car.
quote:Yeah, and I said the age of the vehicle was irrelevant to the quality of the oil—which it is. Just because an engine is old doesn't mean it can (or should be made to) tolerate an inferior oil. And, yes, the old 10w40s (and 10w50s) WERE that bad, and that's the reason GM in the early 80s pulled a 180 and absolutely prohibited their use in GM vehicles.
Originally posted by pruntyc: I said for a 91 it shouldn't matter if it were not SL. For only one case and often changes, come on give me a break. The old oils were not that bad, or we wouldn't have any cars around with any miles on them at all. Like back in the 50's, that needed a over haul, after they got 50,000 ot 70,000 miles on them, and I don't think his oil is that old.
quote:Excuse me, but I never said the oil would hurt his engine. My point has been, and remains, why use an inferior oil (and we don't even know that it is, since I don't think he's posted what he's got) when you can purchase good quality SL rated 10w40 oils (if that's the grade you want to use) at a reasonable price? Why don't you try addressing the topic at hand rather than resorting to ad hominem attacks?
Originally posted by pruntyc: You are talking like a young school boy, that hasn't lived long enough to know much about things. To believe 12 cans of oil, would hurt the engine. If he were to run it all the time from now on, it probably would, who knows for sure, not you or I, sometimes things work differently than we think. Fact is there is people runing engines that have had worse oil in them, and it didn't do them any harm. One case use it. Wouldn't be enough sludge in a case to matter, it would clean out the first or second oil change after that.