Hi, newbie here. In my '04 5.7, I've had a power steering fluid leak for quite some time now. The truck only has 83K miles so obviously I don't drive it often. Before I do, usually I will fill the reservoir up from where it leaked out. At this point, I don't know exactly where it is leaking. Yesterday, I filled it back up but when I drove it, there was a sort of whine and small vibration when I turned the steering wheel left. It was more noticeable at high speeds. When turning right, I didn't notice a problem. My question is, does this seem like power steering or rack/pinion problems? Also, in trying to search this problem, I did notice where I was supposed to use ATF4 tranny fluid rather than the standard power steering fluid that I've been using for years. Don't know if this caused the problem or if I accidently drove it with the reservoir too low. Please help diagnose this problem. Thanks.

 

the power steering COOLER is known to leak (rust)
the low pressure side of the hose.. the clamp is known to break.. cause leaks..

I had both issues. ... around 45,000 miles. on my 2004....

 

^Both of those, yes. If you've been driving it for this long with a leak, why not have it looked at so you know what you need? Yes, you may have done some damage using p/s fluid instead of atf4, probably not, but maybe.