Actually if your engine oil doesn’t turn dark it’s a sign that your oil isn’t doing its job of cleaning the engine especially for diesel engines. Your oil is dark or ‘dirty’ when drained because it has effectively kept soot, dirt, and other deposits and combustion contaminants in the oil and therefore out of your engine. Good quality motor oils like Ultra Lubricants are engineered to extend your engine life and offer maximum protection by holding these contaminants in the oil until the oil and filter are changed so that your engine isn’t damaged by these harmful elements.

Remember that regular oil and filter changes are also important in the prevention of sludge or deposits. And use Ultra Lubricants with detergency and dispersancy additives to ensure your engine stays clean…because when Ultra lubricants keeps harmful deposits in your oil, they can’t damage your engine.