What is the Sound Your Car Makes in Reverse?

Have you noticed that when your manual transmission is in reverse, the car makes a funny sound? If you gain a little speed in reverse, you can really hear the transmission whining about it.

We all have a habit of listening to the sounds our vehicles make. Because of the whine, people think that there's something wrong with the transmission, and bring their car to the shop. However, all cars with manual transmission whine in reverse, some more than others.

Why? The answer is in the gears. The sound is a result of how the gears are shaped in reverse. The forward gears in your transmission are helically shaped, the individual teeth on the gear are curved, but reverse has straight cut teeth.

Because of their shape, a helical gear's teeth are always in contact with the next gear. If you could see the two straight gears moving very slowly you would see a split second where there is a space between the teeth. the whine you hear is because of the tapping of the gears remaking contact with each other. Since a helical gear has long, curved teeth, the two gears are never out of contact, so no tiny taps, and no noise.

But keep listening to your car. Most often when you think it is making a strange sound it is. For more information or to schedule regular vehicle maintenance, contact Reliable Transmission.

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