What's the matter with water in the transmission?
2 Answers
The treatment methods for water entering the transmission are as follows: Clear water entry: Open the bottom of the transmission to pour out the water and oil, then add new gear oil. If the vehicle is driven or operated after water enters, the oil and water will emulsify, making it difficult to separate them. In this case, the transmission needs to be removed and opened for cleaning. Dirty water or water with sediment entry: If sediment enters the bearings, especially the input shaft bearing, all components inside the transmission must be disassembled and cleaned. The transmission mainly refers to the car's transmission, which is divided into manual and automatic types. The manual transmission is mainly composed of gears and shafts, generating variable speed and torque through different gear combinations, while the automatic transmission (AT) consists of a torque converter, planetary gears, a hydraulic torque variation system, and a hydraulic control system.
Transmission water ingress is a fairly common issue, often caused by aging or damaged seals allowing water to seep in when driving through deep water. Alternatively, driving too fast through flooded areas can submerge the ventilation ports, leading to serious problems. Water mixing with transmission fluid degrades the oil's lubrication properties, causing gear rust, seizure, and internal component damage, resulting in shifting difficulties or abnormal noises. I once experienced this firsthand—rushing through a puddle during rain without slowing down led to noticeable transmission shudder upon startup, requiring a tow to the shop for a full flush and fluid replacement at considerable cost. The best prevention is regularly inspecting seal conditions, avoiding water deeper than tire height, and maintaining low speeds when crossing water to minimize risk. Also, ensure filler caps are tightly sealed during fluid changes to prevent maintenance-related water ingress.
