What step must be taken regarding the friction discs during clutch drum assembly?

During the assembly of a clutch drum, it is crucial to line up the friction disc splines properly. This step ensures that the friction discs engage correctly with the clutch drum, allowing for optimal transmission of power from the engine to the drivetrain. When the splines of the friction discs are aligned properly, they can move smoothly without any misalignment, reducing wear and potential damage.

Lining up the splines is important because if they are not correctly positioned, this can lead to improper engagement when the clutch is in use, possibly resulting in slipping or failure to transmit torque efficiently. Proper alignment maximizes the effectiveness of the clutch system, ensuring that it functions as intended during operation.

The other steps mentioned, while important in various aspects of maintenance and assembly, do not specifically relate to the friction discs during clutch drum assembly. Therefore, focusing on the alignment of the splines is essential for a successful assembly and long-term performance of the clutch.