✅ Fixed
Oil change interval truth: 1) Old conventional oil and carbureted engines: 3,000 miles was correct. 2) Modern full synthetic oil in a modern engine: 7,500-10,000 miles is legitimate for normal driving. 3) Severe service (short trips, extreme cold, towing,
Oil change interval truth: 1) Old conventional oil and carbureted engines: 3,000 miles was correct. 2) Modern full synthetic oil in a modern engine: 7,500-10,000 miles is legitimate for normal driving. 3) Severe service (short trips, extreme cold, towing, dusty conditions): use shorter interval — 5,000 miles with full synthetic. 4) Use oil life monitor if your car has one — it uses actual driving conditions to calculate when oil is degraded. 5) Bottom line: full synthetic every 5,000-7,500 miles is safe for most drivers. 3,000 miles wastes money.