Different Viscosity Grades of Diesel Engine Oil: 5W, 10W, and 15W

10W30 CK4 engine oil, 15W40 CK4 engine oil, and 5W40 CK4 engine oil... What are the different grades of diesel engine oil? Is there a difference in viscosity between low and high temperatures? How can we determine which engine oil viscosity grade is right for our car? Let's go over the different viscosity grades of motor oil.

The fluid's resistance to flow determines its viscosity. The viscosity grade of an engine oil indicates how resistant it is to flowing in your vehicle's engine. Engine oil with a low viscosity grade is more fluid and flows more freely. Diesel engine oil with a higher grade, on the other hand, is thicker and flows slower, allowing for the building of a protective coating on engine parts.

An Overview

An engine oil with a low viscosity grade is recommended at low temperatures since it helps the lubricant circulate in your car during a cold engine start.

An engine oil with a high viscosity grade is favoured at high temperatures since it will be more resistant in the engine's critical parts (hot areas). Because it is thicker, it eliminates friction between parts and decreases wear and breakage.

As a result, choosing the appropriate engine oil is critical for your vehicle's engine to perform smoothly. Engine oil decreases friction between parts, cools your engine, discharges pollutants, and protects the engine circuit against corrosion.

Monograde oils

Over a narrow temperature range, monograde oils are employed. They're usually made for older car models. This sort of oil is divided into two categories based on the season in which you will be driving.

There are two types of monograde oils:

Low viscosity motor oil grades begin with a "W" and are typically used in the winter. SAE 0W, 5W, 10W, 15W, 20W, and 25W engine oils, for example.

The high viscosity engine oil types are not designated "W" and are best used in the summer. SAE 8, 12, 16, 20, 30, 40, 50, or 60 engine oils, for example.


Because lubricants with a 5W viscosity grade must flow correctly at lower temperatures than those with a 15W viscosity grade, they are anticipated to be utilised at lower starting temperatures. Most OEMs still favour multi-grade solutions, such as SAE 15W-40, even at higher ambient temperatures since the lubricant flows faster through the engine than a pure SAE 40.

The quality certification or performance level is another key factor to consider when selecting an engine oil. The American Petroleum Institute determines this in the United States (API). The letter "C" and a second letter assigned in alphabetical sequence, starting with "A" for the lowest performance and ending with "J" for the most recent and highest performance, signify the quality levels for diesel engines. Furthermore, there are special OEM performance standards for some applications that are also a condition of the engine's warranty.

However, instead of a 10W or 15W viscosity grade, you can use a 5W viscosity grade to give quicker lubrication to engine components during start-up. There are, however, certain disadvantages to consider. Because the 5W recipe uses a lighter base stock, the diesel engine oilmay evaporate more than a 10W or 15W formula. The 5W may also be more expensive than the 15W since it breaks down more viscosity improves ingredients in the mix.

You might alternatively use a synthetic lubricant with the same viscosity and promises of quality. In general, completely synthetic lubricants outperform conventional mineral oils in terms of detergency and engine protection.

If you don't have access to the OEM's exact quality and viscosity specifications, 15W flows well at ambient temperatures in tropical countries.

Fully Synthetic Heavy Duty Diesel Engine Oilfrom DOXA

DOXA fully synthetic and heavy-duty diesel engine oil has been created and engineered to outperform traditional diesel engine oils. The Fully Synthetic 5W40, 15W-40, and 10W-30 diesel engine oil are formulated to fulfil the most stringent performance criteria of today's high-output, low-emission European and American diesel engines. To provide the highest diesel engine performance, it's manufactured using high-quality base oil and cutting-edge additive technology.All heavy-duty engine oils from DOXA meet or exceed the requirements of CK-4, CJ-4, CI-4 PLUS, and previous classifications.

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