What are the consequences of excessive transmission fluid?
2 Answers
Consequences of excessive transmission fluid: 1. Excessive transmission fluid allows more air to enter, which may cause air blockage at the drain holes on the control valve in severe cases. Poor drainage can lead to gear shifting impacts; 2. When the transmission fluid level is too high, it easily comes into contact with rotating components during driving. The agitation of fluid by rotating parts creates bubbles, and when this bubbly fluid enters the oil pump, it results in abnormal oil pressure and reduced lubrication effectiveness; 3. Contact between rotating components and excessive fluid during vehicle operation can cause fluid expansion and boiling due to high temperatures and high-speed rotation, leading to oil leakage; 4. Excessive transmission fluid can also negatively affect the transmission's efficiency and cooling performance.
As a long-time auto mechanic, I've seen all sorts of troubles caused by excessive transmission fluid. When there's too much transmission fluid, it first starts foaming, which interferes with the hydraulic system, leading to slipping or jerking during gear shifts. You can feel the car speed becoming unstable or hear increased noise while driving. The increased internal pressure can easily damage oil seals, causing leaks—like oil spots under the car. If not addressed promptly, more components can corrode. The oil pump sucking in air can also cause cavitation, which may damage gears or bearings over time, resulting in repair costs that can suddenly run into thousands. Even worse, it can cause the transmission to overheat, affecting its efficiency and shortening its lifespan. I recommend strictly following the manual's measurements when refilling and checking the fluid level every six months during routine maintenance. It's better to have slightly less than too much—otherwise, repairs can be a real headache.
