However, a good starting point is to consult your owner's manual. It will specify the recommended oil viscosity (like 10W-30, 5W-30, etc.) and API service classification (like SM, SN, or newer).
Generally, for a 305 Chevy engine, a conventional or synthetic blend oil with a viscosity of 10W-30 or 5W-30 is a safe bet for most operating conditions. If you live in a very hot climate, a slightly higher viscosity like 15W-40 might be considered, but only if recommended by the manufacturer or a qualified mechanic. If you live in a very cold climate, a lower viscosity like 5W-30 would be better.
Modern oils (SN Plus or higher) offer better protection than older oils. Always check the oil's certification to ensure it meets the requirements of the Society of Automotive Engineers (SAE) and the American Petroleum Institute (API).
Before you choose, consider these points:
* Engine condition: If your engine is older and has higher mileage, you might want to consider using a higher-quality oil, like a full synthetic, to help compensate for wear.
* Driving conditions: Frequent heavy loads or towing will require an oil that can withstand higher temperatures and shear stress.
* Recommendations: Always refer to your owner's manual or consult with a qualified mechanic for specific recommendations.
Don't just rely on internet advice; checking your owner's manual and consulting a professional is crucial for the long-term health of your engine.
