Oil pressure too high on a 2003 Chevrolet 1500 4.3 liter v-6?

I got the truck about a year ago with 120,000 miles,and the pressure would run about 40 psi at idle and about 50 at 3000rpm,but as of 2 weeks ago after a oil change I noticed it now runs the same at idle but 70psi at 3000rpm.I thought maybe it was a bad oil filter,so i did another oil change 3 days ago with no change in pressure.I was also told it could be the oil pressure sending unit,so i replaced it tonight,but again no change in pressure.Is there a problem with my oil pump or any other component,or is this normal operating pressure for a 4.3 v-6?