After verifying proper oil qty. I’d plumb in a manual gauge to verify. If it’s verified to be actual pressure drop, I’d be contacting the installer. If they bought the engine to install they should have the paper work. I’d personally believe if it’s a brand name reman there should be a warranty. The warranty should cover any diagnosis. If the blame falls on the company that rebuilt it let them fix it. If it’s the installer and they put a damaged pan on it that forced the pick up up and possibly cracked the pick up or didn’t set the clearance to the pan correct. Shame on them. They should make it right. You paid your money to get a job done and they didn’t do it correctly, they should stand behind it. Sorry sounds harsh but you paid your hard earned cash. That’s my opinion.
