well first i'd like to say howdy- im a noobie..
My questions stem from my jeep wrangler (97 model year) but with a rebuilt 4.0L that has about 10K miles. I ran synthetic through it for a few thousand miles but it began leaking so i swapped over to dino with no problems. My pressure seems to be low to my standards... at cold startup i get 40-42, cold driving 40-45, warm i get about 20 but the more i drive the lower my idle goes... These figures are the with the current temps ranging from 25-60. In the summer when the temps are between 80-100 with high humidity i get bout 40 on initial start, then like nothing at idle and about 20 driving. Could this be a sensor issue? This is dealing with 10w-30 oil but when swapped into 20w-50 i dont have oil pressure concerns. Should I run 20w-50 or seek other options? Ive been running the STP S8a filter and have tried other filters but havent seen a difference in pressure. For oil ive been running the mobil 1 dino 10W-30 but at next change would like to swap in the 20w-50.... good idea or not? Do rebuilt engines have looser tolerances? Is that why you shouldnt run dino in em? Thanx and sorry for the multiple questions