Can Transmission Oil Be Added to Power Steering Fluid?

[BrooklynMarie]

Transmission oil can be added to power steering fluid, but power steering fluid cannot be added to transmission oil. Below are specific introductions about the two types of fluids: 1. Transmission oil: Automatic Transmission Fluid (ATF) is specifically designed for automatic transmissions. Under normal driving conditions, it should be replaced every 120,000 kilometers, and under harsh driving conditions, every 60,000 kilometers. When replacing, it is best to choose the original ATF, and transmission oils should not be misused or mixed. 2. Power steering fluid: Power steering fluid is a special liquid used in the car's power steering pump. Through hydraulic action, it makes the steering wheel very light, similar to automatic transmission fluid, brake fluid, and shock absorber fluid.

[MacJonathan]

I remember once my friend's car had heavy steering, and he took a shortcut by adding some transmission fluid into the power steering system. As a result, the power steering pump started making rattling noises. The mechanic said some seals were corroded, and it cost over 3,000 yuan to fix. Transmission fluid and power steering fluid are completely different. Power steering fluid requires lower viscosity to lubricate the pump, while transmission fluid contains stronger additives that can damage rubber components. Mixing them can cause short-term heavy steering and may even lead to complete system failure in the long run. I suggest developing the habit of checking the manual before adding any fluid to avoid mistakes—don’t gamble with safety. Regularly inspecting fluid conditions is also crucial; discoloration or unusual odors are warning signs. Repair costs far exceed the price of new fluid—this lesson is costly enough.

[LaLaura]

Having driven for nearly two decades, I deeply understand that fluids must not be used indiscriminately. Transmission oil is specifically designed for gear systems and contains friction modifiers, while power steering fluid is exclusively for hydraulic pumps to ensure smooth steering. Their viscosities differ significantly—mixing them can cause the pump to overheat and seize, leading to steering difficulties or even failure. I once witnessed an accident where a driver used the wrong fluid, resulting in loss of steering control on the highway. Thankfully, no one was injured. Repairs for such mistakes can cost thousands, far outweighing any perceived convenience. During every maintenance session, I remind myself to check the labels and never rely on guesswork. The intended use is clearly printed on every container—just follow the instructions.

[AnastasiaAnn]

I believe the chemical properties of transmission fluid and power steering fluid are vastly different. Power steering fluid has lower viscosity and needs to flow quickly to lubricate the pump; transmission fluid is thicker and contains special additives. Mixing them could cause additive reactions forming deposits that clog pipelines and damage seals leading to leaks. From what I understand, this could make steering heavier or even fail. It's safer to stick with the manufacturer-specified fluid type rather than trying to save money with substitutes. Just make sure to check fluid levels and verify during replacements.