If your motor oil turns black - otherwise, it's golden-amber when brand new - there's usually no reason to panic, as it's normal for it to do so. As your engine oil starts to circulate around the engine, the heat and friction within your car's engine naturally wear down the oil. This is especially so with continuous and repeated heat cycles, like driving and warming up your car, letting it cool, and driving it back, and so on. However, this is a process that takes time. If your motor oil turns black so quickly after an oil change, it's likely that dirt, impurities, and other contaminants from the previous batch of oil have mixed in with the new oil.