Will the Transmission of a Flooded Car Get Water Inside?
3 Answers
Whether the transmission of a flooded car gets water inside depends on the vehicle's condition. Relevant explanations about water entering the transmission of a flooded car are as follows: 1. Vehicle in motion: Generally, as long as the vehicle is still moving and the engine is not turned off, even if the transmission is submerged in water, it will not get water inside. Although the transmission has a vent hole, because the transmission is working, there is pressure inside the housing, preventing water from entering. 2. Vehicle stationary: When the vehicle is parked and the transmission is not working, if the housing is submerged in water, water can enter through the vent hole. In this case, the transmission must be inspected, and the transmission fluid must be replaced. If not replaced within 4 hours, even if repaired three to five days later at a repair shop, transmission failure may still occur after five months.
I still remember the first time I encountered a flooded car situation—I was quite panicked. A waterlogged car can indeed lead to water entering the transmission. Although the transmission housing has sealing gaskets and vent holes, the high water pressure during flooding can force water inside, especially if the water level exceeds half the wheel height, allowing water to infiltrate through air gaps or seams. For example, that time during heavy rain, my car was parked in a low-lying area, and after the water receded, shifting gears became noticeably heavier. Later, when checked, the transmission fluid was found to be cloudy, and internal metal components had started rusting. The mechanic explained that this could lead to lubrication failure, long-term gear wear, and in severe cases, gear-shifting failure. My lesson learned is: after flooding, never start the engine. Instead, call for a tow truck immediately and take it to a repair shop to drain the old fluid, clean the internals, and replace it with fresh fluid. Also, inspect other systems like brakes or sensors to avoid a chain reaction, saving yourself from costly repairs later.
As someone who has dealt with numerous flood-damaged vehicles, I can attest that transmission water intrusion is a common hidden hazard. During flooding, water can seep in through vent holes, seals, or cracks in the casing, especially if the water level rises above the vehicle's undercarriage or the car remains submerged for extended periods. Water mixing with transmission fluid immediately compromises lubrication, causing internal gears and bearings to rust and seize up, leading to increased shifting difficulty or even complete failure to engage gears. In my experience, customers with flood-damaged transmissions often face issues ranging from cloudy fluid to complete transmission replacement, costing thousands. That's why it's critical to avoid driving through floodwater—shut off the power immediately and have the vehicle towed to a professional shop for specialized diagnostics, fluid replacement, and filter changes. For prevention, avoid parking in low-lying areas during rainy seasons or use waterproof covers, and maintain thorough vehicle service records to mitigate risks.
