GotQuestions? Lubricants

Q. I prefer to use a straight 40 wt oil in my Cummins NTC 400 big cam III in the summer. What API is approved? What does Citgo offer in a straight 40 wt.?

November 20, 2013

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A. Actually, Cummins recommended a multi-grade oil 15W-40 in this engine which offered several benefits versus a straight SAE 40 Oil.

However, since you have apparently been using a straight grade SAE 40 for some time with no problems and this is an older engine, CITGO offers a product called CITGARD 600 SAE 40 Heavy Duty Engine Oil.

If you are operating this unit in an area where there are seasonal temperature changes, an SAE 40 does not flow to the engine gallery from the oil pump during cold soaked engine starts below 32F without auxiliary block heating.

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Author Bio

Mark Betner

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Heavy Duty Lubricants Manager

Mark Betner boasts 35 years of experience in the lubricants business. As the Heavy Duty Product Manager for CITGO Lubricants he is responsible for initiating and implementing the marketing of new products and human development programs and oversees communications with the media, trade shows and consumer education.

Prior to this, he was a field sales manager and technical training administrator at an independent lubricant company specializing in heavy equipment lubrication.

Mark earned a master’s and bachelor’s degree in both chemistry and biology from Indiana University. He holds a certification from the Society of Tribologists and Lubrication Engineers and is a member of the Truck Maintenance Council.


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