yes, initial fill, start engine let run a minute then shut off. check level then start and turn from stop to stop. if fluid is FOAMY, let settle, check level and repeat. if its foamy you may be sucking foam into the lines. let truck sit for 1 hour then check.
next, as you know these pumps have a little noise to them, is it a hiss maybe like the accumulator not holding pressure(how is steering and braking???)
could there be debris in system causing high back pressure?
accumulator test: start engine, turn wheel side to side. turn off engine, wait one hour for full test or 2 minutes for quick. there should be two assist brake applications.
need more test info to go further-is steering jerky, hard, soft, surging, poor return, hard brakes, growl at all rpm's, hissing, whatever info you have.