What is a key difference between an open and closed differential?

• A. An open differential allows equal power distribution
• B. A closed differential allows different wheel speeds
• C. An open differential allows wheels to rotate at different speeds
• D. A closed differential is only used in trucks

Answer: (C)

An open differential is designed to allow the wheels on an axle to rotate at different speeds, which is essential for vehicle handling, especially while turning. When a vehicle turns, the outside wheel travels a longer distance than the inside wheel. An open differential enables this by providing a path for the wheels to rotate at different speeds, allowing for smoother cornering and reduced tire wear.

In contrast, a closed differential typically refers to a locking differential or limited-slip configuration, which does not permit the same degree of speed variation between the wheels. This type of differential is more suited for traction in off-road or slippery conditions, where equal power and control are necessary for both wheels. However, it can cause handling difficulties on dry pavement because it restricts the natural rotational speed differences.

Understanding this distinction highlights the advantages of open differentials in everyday driving situations, where smooth turns and equal wheel rotation are beneficial.