My 97 Buick Park Ave naturally aspirated 3800 has 100,000 miles on it. She looks and runs great. I average 33-34 mpg on highway. I love my car and want to keep it going for the rest of my life. I'm 56.
My car has only 1 problem. It has a slight oil leak. I had to put cardboard on garage floor where I park. I have to add ½ qt oil every 500 miles. It's a minor leak. Just a few drops on garage floor every time I park it. This is minor, but annoys me. Otherwise my car is cherry.
I'm using Valvoline 5W30 High Mileage Full Synthetic. My oil drip began after switching to this oil. Is this because I switched an old car to full synthetic or just a coincidence? I thought a high mileage oil would have enough extra seal conditioner to prevent this.
I'm considering options for a solution. Should I next time try Valvoline High Mileage 10W30 Synthetic Blend or go back to a 5W30 or 10W30 conventional?
Is there an easy cheap solution that doesn't require replacing my seals/gaskets?