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Hissing sound on wide/sharp U turns

Not quite a U turn but more like 3 point turn without the backing up, for a wide/sharp U turn to go full circle, turning the steering wheel to the max. It’s typically a left turn in this case as seldom turn wide & around the other way.

Doesn’t happen all the time, might depend on the road surface (level or not, etc.) but when it happens, I hear a faint hissing sound like air leaking or running water in a pipe.

What might this indicate? I don’t suppose it’s normal?

Thats kind of normal, he steering system is fighting itself. When you turn the steering wheel, you move a valve that allows PS fluid to flow into a chamber, thus helping the wheels to turn. When the wheels catch up to the steering wheel position, the valve centers itself and the fluid stops flowing into the cylinder.

When you turn the steering wheel all the way to the stop, you hold this valve open because the wheels cannot move any further. Now the steering system is fighting itself. Back off the steering wheel just a little.

When my car had that symptom, the cure was a brake job. One of the inside pads on the front wheels was almost completely worn out.

One of my driving education instructors used to get on us about turning the wheel all the way until it stops. In some cars, that will make a hissing sound even if the car isn’t moving. Keith’s advice to back off the steering wheel a little bit was the instructor’s advice.

Agree with keith. Hydraulic steering isn’t meant to be operated with the controls hard-over against a physical stop. Back off the steering maybe 5 degrees…just enough to put play back into the system…and you should eliminate the noise, reduce stress on the power steering system, wile negligibly impacting turning radius.

Thanks, that’s good info to know. My instructor never mentioned that to me :frowning: