What Causes Transmission Half-Shaft Oil Seal Leakage?
2 Answers
Transmission half-shaft oil seal leakage may be due to poor quality or aging of the oil seal. Specific causes: Over 90% of oil leakage issues are caused by the rubber sealing rings inside the transmission being subjected to alternating cold and hot temperatures for a long time, leading to the loss of a large amount of plasticizers and softeners in the sealing rings, resulting in corrosion, aging, and hardening problems. Initially, it starts with oil seepage, gradually progressing to oil dripping, and over time, it can cause the sealing ring to break. Solution for this fault: The sealing ring needs to be replaced. If replacing the sealing ring does not improve the situation much, then check if the issue lies with the oil seal.
A couple of years ago, my car had an issue with transmission axle seal oil leakage. Initially, there were some wet, greasy stains under the chassis. Later, after consulting experienced drivers, I learned it was caused by seal aging leading to rubber brittleness and seepage, with high temperatures or bumpy vibrations accelerating crack formation. Another possible cause was improper installation during oil change, resulting in shaft wear and gap loosening. The inspection method isn't complicated: clean the oil stains, drive for several dozen kilometers, then check for new marks afterward. If left untreated, oil leakage could deplete transmission lubrication, damaging gears and leading to expensive repairs. I solved it by spending a small amount to replace the new sealing ring. Daily precautions include avoiding rough roads and using quality oil with regular maintenance to prevent aging. This type of oil seepage is quite common—don't delay until major problems arise.
