I HAVE A 93 LT1 THAT HAS A FEW SMALL OIL LEAKS . MY MECHANIC AND I CAN NOT FIND THE SOURCE. I AM USING MOBIL 1 5-W-30. THE PERSON I BOUGHT THE CAR FROM SAID IT STARTED AFTER THE LAST OIL CHANGE . AT THAT TIME HE SWITCH TO MOBIL 1. HE ONLY CHANGED THE OIL ONCE SINCE HE ONLY HAD THE CAR ABOUT 6 MONTHS AND A 1000K BEFORE I BOUGHT IT. HE DID NOT KNOW WHAT OIL THE PREVIOUS OWNER USED. THE CAR RUNS PERFECT AND I DO NOT RUN IT HARD BUT I DO NOT LIKE THE NAGGING LEAKS. SHOULD I GO TO A HEAVIER OIL? I HAVE NOT DROVE THE CAR SINCE NOVEMBER AND I LOOKED UNDER IT TODAY 1/28/07 AND THERE WERE A FEW SMALL DROPS. ANY ADVICE? THANKS