Is there a limit to how many times a car's doors can be opened and closed? Will it break if it is used more frequently? Does forcefully closing the door affect its lifespan? These are questions often on the minds of car owners.

Car manufacturers subject vehicles to rigorous durability tests in the factory, which typically involve opening and closing the doors more than 100,000 times.

Most ordinary family cars rarely reach such high usage numbers. However, for vehicles like taxis and ride-sharing cars, the door usage can quickly add up. Imagine a taxi driver who receives one hundred orders a day; their car doors might open and close around 200 times daily.

In a year, this can accumulate to over 70,000 cycles, and within a year and a half, it could exceed 100,000 cycles. It's around this point that doors may start experiencing issues.

The most commonly replaced parts in car doors are the door locks. These parts endure significant wear and tear, and over time, they can become problematic. Common issues include broken door handles and door locks that fail to function correctly.

Additionally, some cars may experience door deformation, leading to leaks or rainwater seepage. Car door systems involve three critical components: door locks, door hinges, and door limiters.

Door locks play a vital role in ensuring the safety of vehicle occupants. Their primary function is not only to deter theft but, more importantly, to secure the lives of those inside the car. Door locks must reliably keep the door closed during normal operation to prevent accidental openings.

They also need to allow for smooth and reliable door opening, even in emergencies or when the car's power fails. Therefore, door locks are subject to strict safety standards.

The structure of a car door lock is complex, comprising door handles, locking mechanisms, and various linkages that enable the door to be opened from both inside and outside the vehicle. Repeated use of these components causes metal fatigue over time, leading to deformations or breakages.

Vigorous handling of the door, especially forceful opening, can result in immediate damage, such as breaking the door handle. Front doors, which are used more frequently, are particularly susceptible to wear and tear.

Door hinges are responsible for securing the door to the car body, and determining the door's stability and alignment. Hinges come in two main types: casting and stamping. Casting hinges are thicker and stronger than stamping hinges.

As doors are opened and closed, hinges rotate around a central axis, which can lead to wear and fatigue in the metal. As hinge strength diminishes, the door may deform or sag, causing issues with proper closure.

Car doors contain various other components, including window mechanisms, speakers, door lock motors, and controllers. These parts can also experience wear and tear from repeated door operation.

The shock and vibration generated during door use, especially forceful handling, can accelerate the degradation of door locks, hinges, and limiters.

For typical family cars, these effects are minimal, and the doors may endure for the life of the vehicle. However, for commercial vehicles that experience heavy use, doors are considered wear-and-tear items that may need replacement after several years of operation.

While there is no fixed limit to how many times a car door can be opened and closed, the frequency and force of use can significantly impact the lifespan of the door components. Regular maintenance and gentle handling can extend the longevity of car doors, ensuring they remain reliable and safe throughout a vehicle's life.