The color of the fluid is usually the best giveaway as to its condition. Normally, power steering fluid has a dark red color. Some power steering fluids are clear, so this trick won't always work, but for the fluids that are red, the color is not natural and is added by the manufacturer. Since the color is not natural, it will have a tendency to break down over time. It will also separate where the dye will sink to the bottom of the fluid. So, if the color of the fluid is different from when you purchased it, that is a clear indication that the fluid is no longer good and should be disposed of.

If determining whether or not the fluid is still good through color is impossible, you can also go off a base of two years from date of purchase. Power steering fluid - like anything - will break down over time. When purchasing the fluid, if there is no expiration date on it, it is difficult to determine how long it has been sitting on the store shelf in addition to how long it might be sitting on your work bench shelf. By utilizing a baseline of two years from date of purchase, you can be fairly confident the fluid is still usable. That does not mean you should still not inspect for any separation or changes to the viscosity or color. When determining whether your fluid is good solely based on age, it is important to pay attention to any other changes in the fluid. Should you notice any changes, it is best to just discard the fluid.

We hope you now have a better understanding of how long your power steering fluid will last once opened. We like to consider ourselves the experts when it comes power steering coolers.  If you have any power steering cooler questions, please connect with our technicians in our Ask the Experts forum.