What are the consequences of not changing transmission fluid for a long time?

[Kayla]

The consequences of not changing transmission fluid for a long time include thinning of the gearbox lubricant viscosity, leading to decreased cooling performance and anti-oxidation properties. Here are the relevant details: 1. Lubricant viscosity: Prolonged use causes the gearbox lubricant viscosity to thin, resulting in reduced lubrication performance, decreased sealing capability, increased resistance and wear, unstable pressure, affecting the precision of hydraulic system operation, reduced transmission control accuracy, and impaired shifting precision, smoothness, and response speed. 2. Performance degradation: Deteriorated fluid has reduced cooling performance and anti-oxidation properties, making it prone to issues like high oil temperature, creating a vicious cycle that further shortens the lifespan of both the oil and transmission components.

[LaJune]

From my decades of driving experience, failing to change transmission oil on time can indeed cause major trouble. Over time, the oil deteriorates and gets dirty, losing its ability to lubricate the gears inside the transmission. The result is increasingly severe friction between components and rapid temperature rise. I've seen many vehicles damaged this way, leading to rough shifting or even complete breakdowns. This not only worsens the driving experience—like loud tractor-like noises during acceleration—but may also require major transmission repairs or a full replacement, with costs ranging from thousands to tens of thousands. Regular oil changes cost little but prevent these headaches. My current car gets its transmission oil changed every 60,000 kilometers, and it runs much smoother as a result.

[VonZoey]

As a car owner who has learned the hard way, I'd like to share my personal experience. I neglected to change my car's transmission fluid for a long time, initially thinking it would save me some money. However, after five years, serious problems started to emerge: gear shifting became jerky and shaky, and fuel consumption increased. Eventually, the transmission began slipping and failed completely. The mechanic explained that the deteriorated fluid caused excessive wear on internal components, forcing me to replace the entire transmission at a cost of over 10,000 RMB. This experience taught me the importance of regular maintenance - skimping on small things leads to big expenses later. Now I change the fluid every two years, and my car runs smoothly and worry-free.

[StAlice]

Having worked in an auto repair shop for years, I've seen the consequences of not changing transmission fluid regularly. Aged fluid loses its lubricating properties, and accumulated debris can clog the valve body and cause gear misalignment, most commonly resulting in delayed shifting or shuddering. In severe cases, overheating damages seals, increases fluid leakage, and can lead to complete transmission failure. Early maintenance can prevent this. I recommend checking and changing the fluid every 40,000-50,000 kilometers—don't wait until problems arise.