[p911sc]

The drain plug is located on the oil sump cover which is located on the bottom of the engine. It is centered on the case seam and is about midway front to back of the engine. As Ed says, it is the same size as the drain in the oil tank. Make sure you have a large pan to catch the oil. You are talking about 13.7 quarts if memory serves. Check this link for a picture.
Rick

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