PITGlass

New to the forum and looking for some opinions on an issue I'm experiencing. On cold startup, the oil pressure in my 08 Silverado goes right to 40-45 and as the higher startup idle ceases, the pressure falls down to 10. If I put the truck in gear, the pressure drops to 4, but recovers to 20-25 if I give it just a tiny bit of gas. After the truck comes to full operating temperature, the pressure at idle is 22-24. I had an occurrence the other evening, while in line at the bank where the pressure dropped into the 4 range and I experienced some lifter ticking. The ticking indicates to me that I'm likely not experiencing a bad guage or sending unit, but I'm trying to figure out where to start with this thing. Any suggestions and opinions would be greatly appreciated.