- Armor Blog
- Why SAE 15W40 diesel oil and SAE 10W-30 are the kings of lubricant viscosities
Why SAE 15W-40 oils are preferred for heavy duty
SAE 15W40 diesel oils are commonly used in heavy-duty applications because they offer a good balance of viscosity and temperature performance. Here are some reasons why they are considered the “king” of lubricant viscosities in the heavy-duty market:
- Good viscosity at both high and low temperatures: The “15W” in the name indicates that the oil has a low-temperature viscosity rating of 15, which means it flows well at colder temperatures. The “40” indicates that the oil has a high-temperature viscosity rating of 40, which means it provides good protection at high temperatures. This balance of viscosity ratings makes 15W-40 oils suitable for use in a wide range of temperatures, which is important for heavy-duty applications.
- Meets industry standards: SAE 15W-40 diesel oils meet the requirements of various industry standards, including the API CJ-4 and CI-4 Plus specifications. These standards ensure that the oil meets certain performance criteria, such as wear protection, deposit control, and oxidation resistance.
- Widely available: 15W-40 oils are widely available, which makes them a convenient choice for heavy-duty operators. They can be purchased at most automotive supply stores and are often used in a variety of heavy-duty vehicles, including trucks, buses, and construction equipment.
- Cost-effective: 15W-40 oils are relatively cost-effective compared to some other viscosity grades. They provide good performance for heavy-duty applications while remaining affordable for fleet owners and operators.
Why SAE 10W-30 oils in the passenger car motor oil market are the “kings” of lubricant viscosities?
SAE 10W-30 has been a popular choice for passenger car motor oil for many years because it offers a balance between low-temperature startup performance and high-temperature engine protection. The “10W” designation means the oil has a low viscosity when cold, which allows it to flow easily through the engine during startup, providing critical engine lubrication. The “30” designation means the oil has a higher viscosity when hot, providing a thick enough oil film to protect engine parts at high temperatures and pressures.
Compared to other popular viscosities like SAE 5W-30 or SAE 15W-40, SAE 10W-30 offers a good compromise between low-temperature pumpability and high-temperature protection. It has become a common recommendation for many passenger car manufacturers, and it is readily available in most auto parts stores.
Can I switch to SAE 10W-30 or SAE 15W40 for my car?
While SAE 10W-30 and SAE 5W-30 motor oils are both popular choices in the passenger car motor oil market, it’s important to take a moment and consider if they are the right choice for your engine. One key factor to consider is the climate where you typically drive, as the viscosity of the oil can change with temperature. Therefore, it’s important to choose an engine oil that is appropriate for the temperature range of your location.
Another important consideration is to check the owner’s manual for your car to see if the manufacturer recommends a specific type of motor oil. Some vehicles may have unique requirements that should be followed to ensure proper engine performance and longevity.
By taking these factors into account and choosing the appropriate motor oil for your engine, you can help ensure optimal engine protection and performance.
Do not forget to look for added benefits
Although SAE 10W-30 and SAE 15W40 viscosities are often considered kings of the market when it comes to motor oil, it’s important to remember that not all products with these viscosities are created equal. There are significant variations in product quality and properties based on several factors, including:
- Type of oil: Synthetic, semisynthetic, and mineral oils have different properties, and their prices can vary significantly as well. It’s important to choose the right type of oil for your engine’s needs, based on factors such as driving conditions and engine design.
- Oil brand: Purchasing motor oil from a known and reputable brand is always a safer choice. When you purchase oil from a shady or unknown manufacturer, you risk using low-quality materials or oils that may not meet international standards.
- Additives: When additives are added to engine oil, they can provide additional benefits such as improved fuel economy or better engine performance. However, not all additives are created equal, and some may not be compatible with your engine or may cause other issues.