I got a 91 with 4.9L. I adjusted the steering ,and now the pump whines a little. What do I need to do?

 

What did you adjust ? Adjusting the steering shouldn't make the pump whine. Not just low on fluid, are you ?

 

The adjustment with the locknut on the steering box. The fluid level is full. Steering still has just a little slack , not enough to worry about.

 

Might have it too tight if it's making the pump whine. Back it off a little and see.

 

Backed the adjustment off, pump still whining when I turn the wheel. Do I need to replace pump, or will it hurt anything?

 

Seems that they all whine a little bit - nature of the beast. Some guys have posted that they quieted theirs down by replacing the power steering fluid with automatic transmission fluid. They're both hydraulic fluid, don't know why it would make much difference (maybe viscosity), but apparently it does.
Mine makes a little noise, but just a very little and it seems only when I'm turning the wheel while stopped (which I guess is when the pump is working the hardest) so I just ignore it. Not worth worrying about unless it was to start getting real loud.
Of course, clean fluid is important.