What Causes Transmission Slippage?

[JustinFitz]

Transmission slippage may be caused by wear, looseness, breakage, or loss of the gearshift lever's positioning pin, resulting in loss of control and erratic movement. Below are specific causes and solutions: Specific causes: Worn or failed interlock mechanism of the shift fork shaft; excessive wear and looseness of the gearshift lever ball head. Gears, gear rings, or gear sleeves becoming conical due to wear along the tooth length, causing disengagement under axial forces generated during operation. Excessive wear of shift fork shaft grooves, locking pins, and other components; bent or deformed shift forks, or excessive wear between working surfaces and gear ring grooves. Loose rear fixing nut of the second shaft, leading to axial movement. Loose or disassembled synchronizer locking pins, causing cone surface failure. Solutions: When a gear disengages, re-engage the gearshift lever into that gear, then remove the transmission cover to inspect gear meshing. If the gears mesh properly, the issue lies in the shift mechanism. Manually test the positioning device of the disengaging shift fork. If positioning is poor, remove the shift fork shaft and inspect the positioning ball and spring.