For one reason or another the OEM often leaves the time to replace power steering fluid off of the maintenance guide. This is mostly to keep cost of ownership down. One way to know when it’s time to replace your power steering fluid is by mileage. No power steering fluid is lifetime, and should at a minimum be changed every 50,000 miles. Changing the fluid out based on mileage is considered preventive maintenance.
In addition to mileage-based maintenance, power steering fluid should also be changed out any time a component in the power steering system fails or gets replaced. The number one cause of pre-mature failure in power steering components is contaminated fluid. The fluid becomes contaminated either by a leak in the system allowing particles in, or by an internal failure of a hard part resulting in debris in the power steering fluid.
Whenever changing out a failed power steering hard part - whether it's the power steering pump, rack and pinion, steering gear box, or power steering cooler - change the power steering fluid.
Signs you Need to Change Power Steering Fluid
There are a number of different signs you need to change the power steering fluid in your vehicle. Just like any fluid in your vehicle, the power steering fluid has a lifespan. With all vehicle fluid lifespans, you should always start by checking for OEM recommendations. These recommendations can often be found in the vehicle's owner's manual.