How much power steering fluid is needed?

Ummm, no. If you're constantly adding, you my friend have a problem. Get it checked. That is a possible OOS failure.

Reservoirs are supposed to hold liquid, not let it disappear.

 

You need to add Power Steering Fluid while the truck is running and move the steering wheel from time to time to alleviate the air pockets.

Yes, you might have a leak if all of it leaked out.

 

You think.. you keep filling it up. Yes there is a leak somewhere

 

Power steering should be a sealed system. If you have to add fluid on a regular basis, its leaking out somewhere. If you can't see an external leak anywhere, I would wager the input shaft seal is leaking on the pump, putting the power steering fluid into the engine oil.

What you read earlier is true, when you refill the system after a repair or fluid change, you will need to fill the reservoir, run the truck for a few seconds, top it off, repeat and then cycle the steering full left and right and keep topping off until the level no longer drops.

 

Is your engine oil over filled?

 

If the leak was not on the outside of the pump then you need to sample your oil and test for power steer fluid in oil. How much over full was your oil? Bearing wear issues in very near future if not checked and just let it stay in crank case. Will dilute your viscosity also.