Due for an OCI and looking for recommendations on oil type and viscosity. My father bought the truck new and sold it to me 7 years ago. Manual calls for 5W-30 and the engine has only seen conventional 5W-30 oil every 5K miles. Dad used Fram filters and I use Wix. Currently has 125K on it with no mechanical problems besides brakes but that's in Mechanical forum and not related! This truck gets 4-5K miles on it a year only being used once or twice a week for short commutes (8-16 miles) or back and forth to hunting camp 80 miles so mixed use. May sit 2 weeks at times not being used at all. Noticed the last two years I have been having to add 1 1/2 to 2 qts between oci's. No oil spots in the driveway where she sits so must be burning it. I live in Central PA where temps vary from sometimes below 0 to 100 degrees F. Please make a recommendation and why.......thanks.