In the 1950s, motor oil started to come in grades. Some grades were formulated to work better in cold weather, while others helped keep hot engines lubricated more effectively. Today, with our ...

The numbers and letters on a bottle of motor oil can look like gibberish if you aren't sure how to decode them. 5W-30, 10W-40, 0W-20... What's this supposed to be telling you? Does the "W" stand for ...