Why Should Transmission Fluid Not Be Changed After Exceeding 100,000 Kilometers?

[DiAmy]

The reasons for not changing transmission fluid after exceeding 100,000 kilometers are as follows: 1. Damage to components: Not changing the fluid for 100,000 kilometers can cause severe wear and tear on the components, and during winter, the transmission can become very unresponsive. 2. Prolonged lack of fluid change: This can lead to sluggish acceleration, increasingly higher fuel consumption, and vehicle shaking. In severe cases, it can cause the transmission to overheat and become irreparable. Relevant information about transmission fluid is as follows: 1. Transmission fluid: It is a lubricant that keeps the gear system clean, ensuring the transmission works properly and extending the lifespan of the transmission system. 2. Classification: Automatic Transmission Fluid (ATF) is specifically designed for automatic transmissions; Manual Transmission Fluid, commonly referred to as gear oil, is categorized into five grades (GL-1 to GL-5) by the American Petroleum Institute based on its quality level.

[Hugh]

My car's transmission fluid hasn't been changed for 120,000 kilometers, mainly to save money. Nowadays, transmission fluids are all synthetic, with much longer lifespans than older types. If you mostly drive on highways, the fluid degrades slower and can easily last over 100,000 km. Each fluid change costs at least a few hundred bucks, and the savings are enough for gas. Plus, the maintenance manual says the replacement interval can be extended based on driving conditions, so I just check if the fluid level is adequate and the color hasn’t turned black—otherwise, I don’t bother. Of course, if you frequently deal with stop-and-go city traffic, the fluid quality deteriorates faster, so it’s best not to delay the change too long in that case.

[DiEmiliano]

As someone who frequently researches car maintenance, I believe the reason transmission fluid can go over 100,000 kilometers without needing replacement is due to the enhanced anti-aging properties of modern synthetic formulations, which perform reliably under smooth driving conditions. Manufacturer tests show that with improved low-temperature fluidity and thermal stability, the oil is less prone to oxidation or carbon buildup, naturally extending its service life. Additionally, new cars generally adopt sealed transmission designs, reducing contamination risks and lowering the demands on the oil. However, I still insist on regularly checking transmission performance, such as whether gear shifts are smooth, to avoid regretting it only when a malfunction occurs.

[VonAurora]

I've been driving for decades. In the early years, I changed transmission fluid frequently, but with advancements in new fluid technology, my car has now run 130,000 kilometers without a change. Synthetic materials make the fluid more durable, and it doesn't degrade easily under normal city driving conditions. The condition of the fluid mainly depends on driving habits—drivers who do a lot of steady-speed cruising can extend the interval appropriately. But remember, if you notice unusual noises or jerking, it means it's time for immediate attention.