For high-end cars, you should consider replacing the fluid every 35-40 thousand miles. [1] X Research source
Your reservoir usually has a labeled cap or a picture of a steering wheel. If you are having trouble locating this semi-transparent plastic tank, check your owner’s manual.
Flush your fluid if it smells burnt, looks dark brown or black, and/or has shiny, metallic bits in it. [3] X Research source Refresh your fluid if it is darkly colored, your owner’s manual recommends it, and/or if you do frequent towing or high-weight driving. Your fluid is fine if it is lightly colored, dark without metallic bits or chunks, or was replaced in the last two to three years. [4] X Research source
Place a disposable pan right under the location of the catch tray to capture the fluid as you flush it. If you are extra car savvy, make sure you disconnect the line that goes from the power steering rack to the reservoir. While not strictly necessary, this will remove more fluid and lead to a better flush. [7] X Research source
Be ready for the fluid to flow as soon as you unhook it. Gloves, eye protection, and long sleeves are recommended.
Have your friend turn the wheel back and forth as you pour. This will help remove air from the lines. The fluid will likely bubble as you fill it. This is good, as it represents the air being flushed from the system.
If your fluid is dark or you are losing sleep worrying about your car, this simple procedure will refresh your fluid for the foreseeable future. [13] X Research source
Many cars don’t even recommend changing this fluid — you’ll be ahead of the game if you even do this.
