I got a re-manufactured engine for my 1990 Silverado with a 305 from Jasper engines. Darn thing runs fantastic. I ran it for the last 3 years on Mobil super high miles 5W/30. It never leaks a single drop of anything. I want to try 5 quarts of Mobil -1 5 W/30 synthetic, I know there are a lot of attitudes about Dino oil and synthetic, what do you think ? I always use a AC Delco PF-35L 0r a PF1218CL and would you believe the filter fits my 2014 GMC Terrain as well as my 1990 & 88 Blazer 350?