Read this on a Ford Truck oil/lube forum! (i was all over the place tonight!)
Let a drop of oil fall onto a paper towel (single ply) from the dip stick. Let it spread onto the paper towel, and shine a flash light from the back so it illuminates the oil drop. If it is still good, it will be even in color and there will be no flakes. if it is bad, well it will be obvious.
Just wanted to share this with you all. Not very scientific....but made for a good read!