What does a worn out shift fork typically affect?

A worn out shift fork primarily affects gear shifting accuracy. The shift fork is responsible for moving the synchronizers and gears in the transmission to enable smooth gear changes. When the shift fork is worn, it may not engage the gears properly or may fail to align the gears effectively when shifting. This could result in missed shifts, grinding noises, or difficulty moving into certain gears, all of which directly impact the accuracy of gear shifts. Proper alignment and movement of the fork are crucial for the seamless operation of the transmissions, hence a worn shift fork disrupts this function.

The other options, while related to the operation of the vehicle, are not directly influenced by the condition of the shift fork. For instance, clutch engagement, vehicle alignment, and fuel efficiency do not rely on the performance of the shift fork in the same way that gear shifting does.