All of these fluids will have different life expectancies. The manufacturer sets a schedule for when each fluid should be changed, and these lifespans are usually either time or mileage based. The OEM tests each fluid for breakdown and determines when it stops performing its job to the expected level. In order to determine what the lifespan for each fluid is, it is recommended you review your owner's manual. This is a good way to know when it’s time to replace your car’s fluids.

The problem with following the OEM’s suggested schedule is that more and more OEMs are focused on keeping the general cost of ownership down, and making claims like “Lifetime Fluid”, or “Never need replacing”. Then they only warranty the product for 3 years or 30,000 miles. The thought that any fluid can last forever is unrealistic; therefore, it is suggested that at minimum all fluids are replaced at 100,000 miles. Don’t forget to track your car fluid replacement schedule.

The most overlooked fluid on the vehicle is often the power steering fluid. Power steering fluid goes through tremendous amounts of adversity every time the vehicle is driven. The power steering fluid can reach temperatures in excess of 250 degrees while lubricating and cooling the entire power steering system. Oddly enough, power steering fluid is rarely given a lifespan or suggested replacement interval. However, we recommend that the fluid is changed every 50,000 miles in order to prevent failure on all power steering components. We hope this answers your question about when to replace the fluids in your car.