Should I Switch From 0W-20 To 5W-30 Engine Oil?
A reader asks: 0W-20 motor oil is suggested for my car. Should I use 5W-30 instead? Will 5W-30 protect my engine better than 0W-20?
Our answer: It is a commonly held belief that 0W-20 engine oil is somehow deficient and that using a thicker viscosity will be beneficial. However, the idea that using a thicker motor oil will prolong engine life is a misconception.
It’s important to note that 5W-20 and 0W-20 motor oils have been used extensively for the past quarter century. Over that time, there is no evidence to suggest that engine life was compromised by 20-weight motor oils.
The Main Reason To Stick With 0W-20 (if suggested by your manual)
Let’s cut right to the chase. Manufacturing tolerances and engine oil passages are now extremely tight. Today’s engines are designed to accommodate very thin engine oils. It is vitally important to use an engine oil viscosity that will effectively circulate through these tight passages. Therefore, going with a thicker viscosity might not be an automatic route to improved wear protection or proper operation.
Rest assured that today’s motor oils offer anti-wear technology that is designed to withstand the high-heat and high-horsepower of today’s engines.
Go With Synthetic Motor Oils
If you are hesitant about using 0W-20 engine oil, then put your mind at ease by using a high-quality synthetic oil. A good synthetic 0W-20 has a greater capacity to fight extreme heat, stay in grade and prevent metal-to-metal contact. We have had great performance from our world-class AMSOIL Signature Series Synthetic 0W-20 Motor Oil.
Important Notes About Today’s Engines
Government mandates have forced auto makers to place an ever-increasing emphasis on emissions and fuel economy. Many vehicles now have an engine with smaller displacement, but yet generate very high horsepower. This is thanks (in many cases) to turbo-chargers, which are now commonplace.
The challenge for modern motor oil is the higher stress of very high-horsepower and torque, relative to displacement. These smaller engines also contend with hotter operating temperatures, turbo-chargers, high-cylinder pressures and heavy bearing loads.
Fuel economy mandates have motivated car makers to migrate to thinner and thinner engine oils to reduce fluid friction. This is why we’ve seen the move from 5W-30 to 0W-20 and even thinner grades like 0W-16, 0W-12 and 0W-8 (in rare cases).
Conclusion
The auto industry is still reaching for engineering perfection in the quest to make big horsepower from smaller engines. However, the motor oil industry has been working overtime for decades to provide the best possible wear protection in these ever-changing operating conditions.
