What to know
- If you need to top up your oil level and only have a different grade available, mixing a small amount is acceptable.
- If possible, top up your oil level with the same grade of oil that is already in your engine.
- Schedule an oil change with a qualified mechanic who can ensure the correct oil grade is used.
When it comes to vehicle maintenance, choosing the right motor oil is crucial. Motor oil’s viscosity, measured in SAE (Society of Automotive Engineers) grades, determines its thickness and flow characteristics. Two common oil grades are 5W-20 and 5W-30.
5W-20 oil is thinner and flows more easily at low temperatures, making it suitable for cold climates. 5W-30 oil is slightly thicker and offers better protection at higher temperatures, making it more suitable for warmer climates.
Can I Mix 5W-20 Oil with 5W-30?
The short answer is yes, you can mix 5W-20 and 5W-30 oils in a pinch. However, it’s not recommended as a long-term solution.
Mixing Different Oil Grades
Mixing different oil grades can create an intermediate viscosity that may not meet the manufacturer’s specifications for your vehicle. This can lead to potential issues such as:
- Decreased engine protection
- Reduced fuel efficiency
- Increased wear and tear on engine components
When Mixing Is Necessary
There may be rare situations where mixing different oil grades is necessary, such as:
- Emergencies: If you run out of the correct oil grade, mixing different grades is better than running your engine without oil.
- Top-ups: If you need to top up your oil level and only have a different grade available, mixing a small amount is acceptable.
Mixing Ratios
If mixing different oil grades is unavoidable, follow these guidelines:
- Mix in small quantities: Add only enough oil to reach the recommended level.
- Avoid excessive mixing: Do not mix more than 20% of a different oil grade.
- Change the oil as soon as possible: Schedule an oil change to replace the mixed oil with the correct grade.
Long-Term Consequences
Mixing different oil grades for an extended period can have detrimental effects on your engine. It can lead to:
- Sludge formation: Mixing oils with different additives can create sludge that clogs oil passages.
- Premature wear: Improper viscosity can cause excessive friction and wear on engine components.
- Reduced lifespan: Mixing different oil grades can shorten the lifespan of your engine.
Other Considerations
- Manufacturer’s Recommendations: Always refer to your vehicle’s owner’s manual for the recommended oil grade and change intervals.
- Oil Additives: Mixing oils with different additives can affect their performance.
- Synthetic vs. Conventional Oils: Mixing synthetic and conventional oils is generally not recommended.
Safe Alternatives
If you need to change your oil but don’t have the correct grade, here are some safe alternatives:
- Use a compatible oil grade: Check your owner’s manual for a list of acceptable oil grades.
- Top up with the same oil grade: If possible, top up your oil level with the same grade of oil that is already in your engine.
- Get a professional oil change: Schedule an oil change with a qualified mechanic who can ensure the correct oil grade is used.
Information You Need to Know
Q: Is it okay to mix 5W-20 and 5W-30 oils in a diesel engine?
A: No, diesel engines require specific oil formulations. Mixing different oil grades can cause engine damage.
Q: What happens if I mix 5W-20 and 10W-30 oils?
A: Mixing oils with different weights can create a viscosity that is too thick or too thin for your engine. This can lead to reduced engine protection and increased wear.
Q: Can I mix synthetic and conventional oils?
A: While it’s generally not recommended, mixing synthetic and conventional oils in small quantities (less than 20%) is unlikely to cause significant harm.
Q: How often should I change my oil after mixing different grades?
A: Change the oil as soon as possible, preferably within 500-1,000 miles of mixing different grades.
