Yes, you can put synthetic oil in your car, and for most modern vehicles, it is the recommended choice. The key is to ensure the oil meets the viscosity grade and performance standards specified in your owner's manual. Synthetic oil offers superior performance and protection compared to conventional oil. It flows better in extreme cold, resists breaking down under high heat, and generally allows for longer intervals between oil changes. For older cars that have always used conventional oil, a switch is often fine, but it's wise to monitor for leaks, as synthetics' superior detergency can clean away deposits that were sealing minor leaks.
The primary advantage of synthetic oil lies in its molecular uniformity and engineered additives. While conventional oil is refined from crude oil, synthetic oil is chemically constructed to have molecules of a consistent size and shape, which reduces friction and provides more predictable lubrication. This translates to several tangible benefits, particularly regarding viscosity—the oil's resistance to flow. A multi-grade oil like 5W-30 must perform across a wide temperature range, and synthetics do this more effectively.
| Feature | Conventional Oil | Synthetic Blend | Full Synthetic |
|---|
| Base Oil Composition | Refined from crude oil | Mix of conventional and synthetic base oils | Chemically engineered compounds |
| High-Temperature Stability | Good | Better | Excellent (resists oxidation and sludge) |
| Cold-Weather Flow (e.g., -30°C) | Fair | Good | Excellent (easier cold starts) |
| Typical Oil Change Interval | 3,000-5,000 miles | 5,000-7,500 miles | 7,500-15,000+ miles (check manual) |
| Engine Wear Protection | Good under normal conditions | Improved | Superior under extreme stress |
| Cost | Lowest | Moderate | Highest |
Before making the switch, the most critical step is to consult your vehicle's owner's manual. It will state the required API (American Petroleum Institute) service rating (like SN, SP) and viscosity grade. Using an oil that meets these specifications is non-negotiable. For a high-mileage vehicle, you might consider a high-mileage synthetic oil, which contains conditioners to help keep seals pliable and reduce the chance of leaks. Ultimately, while synthetic oil costs more per quart, its extended drain intervals and enhanced engine protection often make it a more cost-effective and beneficial choice in the long run.
