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Was a Dodge Ram Harmed Since CJ-4 Oil Not Used
Ask Your Stickiest Question. . . Or ask us something you’ve always wanted to know about using our products. We’ll sort through all the submissions and present the best questions to our automotive experts. We'll share the questions and their answers here.
Was a Dodge Ram Harmed Since CJ-4 Oil Not Used
I have a 2001 Ram diesel truck with 57,000 miles on it. I've used Mobil 1 15W-50 since it had 500 miles on it. I will be switching to the new 5W-40 turbo diesel truck. Did I do harm to my engine because the 15W-50 was not CJ-4 certified?
-- John Suanno, Jackson, NJ
No.  CJ-4 is a certification valid for 2007 and newer engines due to new EPA requirements.  You should be fine.
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