What is the difference between 10w30 and 5w30 engine oil?
3 Answers
10w30 and 5w30 engine oils differ in their temperature adaptability: 10w30 engine oil is suitable for temperatures above -18 degrees Celsius, while 5w30 engine oil is suitable for temperatures below -18 degrees Celsius. The functions of engine oil include: lubrication, auxiliary cooling, cleaning, sealing and leak prevention, rust and corrosion prevention, shock absorption, and anti-wear. The method for adding engine oil is as follows: 1. Lift the car, remove the protective plate, and place a container of about 10 liters under the oil drain screw; 2. Unscrew the oil drain screw, use an air gun to blow into the oil filler port for two minutes, tighten the oil drain screw after draining, and wipe with a tissue to check for leaks; 3. Reinstall the protective plate, lower the car, and use a funnel to add engine oil into the oil filler port.
The difference between 10w30 and 5w30 engine oil mainly lies in the first number. 5w indicates better fluidity in cold weather, allowing the engine to start more smoothly in winter without hesitation. I live in the north where temperatures drop below -10°C every winter. When I used 10w30, the engine would make loud groaning noises during cold morning starts and required prolonged warm-up. After switching to 5w30, it starts smoothly with just one ignition - extremely worry-free. The "30" viscosity rating is identical for both at high temperatures, providing similar engine protection, making either suitable for summer use. If your winters are refrigerator-cold, choose 5w30 for better antifreeze performance; in warmer southern regions, 10w30 works fine. More expensive oil isn't necessarily better - always check your vehicle manual and local climate conditions before switching to avoid problems. My neighbor once tried saving money with cheap oil, resulting in severe engine wear and costly repairs - a hard lesson. Also consider driving habits when changing oil: 5w30 offers slightly better fuel efficiency for frequent highway driving, though the difference is minimal.
The biggest difference between 10w30 and 5w30 lies in their low-temperature performance. 5w has lower flow resistance during cold starts, allowing it to lubricate engine components faster and reduce wear. I use my car for daily commuting and am quite data-driven. I've noticed that 5w30 slightly improves fuel efficiency compared to 10w30, as the lower viscosity makes the engine run smoother—saving about half a liter per 100 km. However, it's only a minor improvement, so don't expect miracles. At high temperatures, both have the same 30 viscosity, offering similar protection. The key factor when choosing oil is the car's age: newer or modern engines often recommend 5w30 in the manual, while older cars specified for 10w30 shouldn't be forcefully switched, as it might cause seal leaks. I keep multiple oil types in my garage and switch seasonally: 5w30 is a must in winter to prevent cold-start issues, while summer is more flexible. Regular oil changes matter more than the brand—stick to every 8,000 km to avoid sludge buildup and engine warnings. Saving on maintenance isn't worth it; choosing the right oil ensures long-term engine care.
