1999 Jeep Laredo oil pressure

I have a 1999 jeep grand cherokee laredo with a inline 6 4.0L, I started to have a high oil pressure indication, its pegging out at over 70psi when running and 60psi at idle, use to be at around 50psi at idle and 60psi when running, I changed the oil and filter and no change, also my overhead computer indicator for my mile per gal. seems to reading off/high then it use to be at around the same time that I noted the high oil pressure, there is no other indication that the car is not running correctly.