Cat C-7 diesel oil viscosity
I have a 2004 Cat C-7 in a 36' Meridian which I have been using Rotella 15W-40 oil in it since new 68,000 miles back. Seems I remember reading somewhere the thought was that 10W-30 was better for the...
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You can use Cat's DEO-ULS 5W-40 Synthetic which exceeds the performance requirements of Caterpillar ECF-3 (Engine Crankcase Fluid Specification), ECF-2, and the API CJ-4 category, if you want to use a synthetic. Mobil 1 Delvac 1 ESP 5W-40 meets the same specs and shows up in new oil analysis as almost identical.
