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Damage to power steering?

I’m hoping someone can settle a disagreement I’m having. I say you shouldn’t hold a vehicle’s steering wheel at it’s ends as it damages the power steering system, as evidenced by the often hissing sound. My friend says there’s no damage as the manufacturers designed the system to handle this and everyone does it. Can someone tell us if it’s damaging and why? Thanks.

First of all, everyone doesn’t do it.

It’s very rare for me to ever reach the limit of steering travel in either direction. I doubt that damage would result from reaching these limits once in a while, but I certainly wouldn’t make a habit of holding the steering wheel at the limit for any length of time.

There’s a pressure relief valve in the PS system, which is designed to prevent damage on the few occasions when you might reach the steering limits, but I don’t think it’s designed for continuous use.

Where does your friend drive that requires such tight turns?

I can’t see any way it could damage the system. But I also can’t see why anyone would do this.

Newer road designs with the islands in the middle often do require tight U-turns at intersections to get to one’s destination on the other side of the road, and if this is what you’re alluding to as holding it there it’s totally harmless. And made necessary by the road design, at least on 101A west of exit 7…

On older cars the belt would start squealing, indicating you are doing something bad. On newer cars, with the right pressure relief valve, the squeal is mostly gone. But it is still hard on the pump, and an unnecessary activity.

Perhaps where I drive…see my following post.

if it was truly doing damage then would they not put a relief valve in? but they DO put one in, so whats the harm? i personally am aware of the hissing of the relief valve opening, and try to minimize that. maybe some people aren’t aware of hydro overloading and don’t care. but if there was no pressure relief there would be ALOT of blown steering racks.

My shop manual says not to hold it to the stop for more than a few seconds in the section for bleeding air out of the fluid. Over heating can result. In the owner manual it says:

Your vehicle is equipped with power steering. Power steering uses energy
from the engine to help steer the vehicle.
To prevent damage to the power steering pump:
? Never hold the steering wheel to the extreme right or the extreme left
for more than a few seconds when the engine is running.
? Do not operate the vehicle with a low power steering pump fluid level.

What does it say in your owner manual and what does it say in your friend’s?

The steering stops should make contact at the same time for both wheel when the extreme is reached in right or left turns. Should; but, sometimes from wear or (mis)adjustment, the stops may not contact simultaneously. When they don’t contact simultaneously, excessive pressure may be applied to a ball joint or tie-rod end.

We drive in Boston. 'nuff said.