possible oil pump ?
1998 ranger 4x4 5speed 181000 mi. vehicle is new to me checked this truck out with a loud muffler so didnt hear this until i quieted her down with a new one. hear a crackling noise when i start her cold, comming from the lower passenger side just for a second or two. as i start her i watch the oil pressure gauge and it hesitates for that amount of time then jumps to 40 psi and stays there steady, does not make a sound when shes warm, only cold. running 5w 30 in her right now, penzoil conventional and yes its cold outside, about 20 degrees any thoughts would be appreciated, by the way i have a feeling the engine thats in her right now is a sub from salvage. junkyard writting 04/05/40mi and if so i figure its got around 110,000 mi on the engine.