I get a lot of questions from car owners asking if something is wrong with their transmission because it makes a whining sound when they drive in reverse. If you've driven anything at all in the last three decades, chances are you've heard a manual transmission humming in reverse. You're also probably used to this noise, and not alarmed. Whether you fit into the category of the worried or the lulled, rest assured there is nothing wrong with your transmission. To prove it, here's the technical explanation of reverse gearing to explain it all.