Hello everyone, saw the thread on a power steering pump rebuild and all the useful information that came from it and I figured I'd get some input on the power steering hiss noise that plagues a lot of the newer Imprezas 2.5i and STI (from my observation, please chime in if this has always been a problem)

Did some research into this issue and found that it was "normal" (proper fluid levels, no leaks) for there to be a hissing noise coming from the power steering pump especially during parking situations. What alarmed me though is a whole thread I found dedicated to people installing a power steering fluid cooler that claimed to eliminate the hissing noise and prolong the life of the power steering pump along with any associated seals. Could this be a key piece of "maintenance" that will prevent something more major such as a steering rack seal leak down the road (theory being that the boiling power steering fluid is harder on seals)?

0529101841b.jpg7389594108_e804d4b6f0_b.jpg

I'm usually not a fan of these DIY mods that stray from the factory design but could this really be beneficial for the car? Also it seems most of the people that performed this lived in warmer States down south. Can the fluid become too cool to circulate efficiently during our harsher winters?

Any input into this will be much appreciated