If your vehicle is showing power steering fluid reservoir needs constant refilling, here are the most likely causes and the parts you'll need to fix each one.
The high-pressure hose carries fluid from the pump to the steering rack. The rubber degrades over time or the metal crimps fail, causing significant leaks under pressure. Missing or pinched O-rings during installation are also common culprits.
The low-pressure return hose routes fluid back to the reservoir. The rubber can become brittle and crack, or the clamps can loosen, leading to a steady drip.
The seals inside the steering rack wear out, allowing fluid to leak into the accordion-style rubber boots on the tie rods. You may not see a puddle immediately until the boots fill up and leak.
The internal seals or the main shaft seal on the power steering pump can fail, causing fluid to leak down the front of the engine or get slung around by the pulleys.
The plastic fluid reservoir can crack from heat cycles and age, or the rubber seal inside the cap can flatten out, allowing fluid to seep out and run down the hoses.