Just recently had the injectors rebuilt on a 7.3 powerstroke diesel engine F250SD. with it all back together I noticed when I checked the oil level it was slightly above the max level, so it loosened the drain plug to drain off a quart or so. Much to my surprise it initially drained about half a cup of what appeared to be clear water before draining any oil. At the same time I had recently noticed a small coolant leak around the thermostat housing, which is known to be a problem on this motor (replaced the housing with the billet aluminum version which fixed the leak) and there are no subsequent signs of coolant loss. I am guessing that somehow this coolant leak somehow managed to get into the oil sump/pan. If in fact the water in the oil was from the coolant leak, it appeared to be clear water, making me believe an equal amount (half a cup) of antifreeze was absorbed by the oil. If I hadn't just done a $90 oil/filter change with 16 quarts of full synth oil I would just go ahead and change it Now my question is, 1) would a UOA identify if there was antifreeze in the oil? and 2) should I be concerned about about a small quantity of antifreeze (say half a cup) in 16 quarts of oil, knowing that antifreeze is not a lubricant?.