I'm experiencing a whoosing or a noise that sounds like air or vacuum leaking when turning the steering wheel on my '97. It seems to be more pronounced when the A/C is running. Could the fluid need changing? If so how do you flush it and how much fluid does it hold?

 

My suggestion is to add some Lube-Guard PS additive, great stuff from most auto parts. You will have to remove a little fluid to make room for the Lube-Guard, a turkey baster works great.

 

Do you think I should change out the fluid first and then add the additive?

 

Take a look at the fluid when you suck it out, if it looks bad change it. Without getting into a hassle the only easy way to change it is to use the same turkey baster method to suck out as much fluid as possible, add some new, Valvoline Synpower is good. This will only change a fraction of the oil, you must start the engine and do this a few times before it will be close to 100% new fluid. It will still take less than a quart to change it four times.
Some people disconnect a PS hose then start the engine in an effort to get all the fluid out at once. Makes a mess and takes longer than several times emptying the reservoir.

 

I can't seem to find Lube Guard. Will Lucas additive work as well?

 

Never tried Lucas but assume it will work.
Surprised you can't find Lube-Guard, it's popular and great stuff.

 

Forgot to post results. I emptied the reservoir 2 times and refilled with Valvoline Synpower. The old fluid felt kind of thin. Anyway the noise went away and the steering feels tighter. I didn't use any additives as the bottle of Synpower says it contains conditioner.