I`m coming up on a routine service interval, and I`m thinking its time to flush and replace the power steering fluid. From past experience I have removed the high pressure line, started the vehicle, and had someone turn the wheel side to side a few times until air started coming out. I`m wondering if anyone has a better method?

 

Also, What about fluid? Anyone try any high mileage fluids with seal conditioners? or just strait PS fluid?

Actually its the low pressure return line you unhook. Then pump it out of the return line into a waste bucket. I normally go lock to lock with the front axle jacked up to attempt to push out as much of the old fluid. Then once that is done then flush on load of fluid through to clean up a bit. Then rehook and fill and top off. After this point shut it down allow the foam to settle before driving. 

 Yes I meant the low return line.. So to flush the steering gear along with the whole system. What do you think of the fluids with seal conditioners? I`ve seen Valvoline and Lucas both make a PS fluid with conditioners.

I still have memories of working on the old purple "99" where everything associated with the PS was leaking.. Pump, Hoses, Gearbox, hydro boost, that was a nightmare. I can`t imagine how that truck got that bad. 

I would not use that stuff at all. Just use the fluid designed for your system and change it at the proper time. I'm going to cross 300k miles and still got my factory power steering pump and gear box yet... No leaks.