tolerances keep getting tighter in engines. Any brand, gas or diesel. When Ford came out with the 4.6 engine and 5W20 oil, it was hard to convince some of the old school people no not use 10w30 or 10w40, till they had their oil filters balloon up and leak. Case IH has come with with 10W30 diesel oil now. Do you know how hard it will be to convince all these farmers that the 15W40 they have been using for generations is now replaced with a lighter oil.
David & Lynn
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