Understanding OEM Guidelines for Oil Selection: A Complete Guide

There’s a common saying that transport is the lifeline of a nation's economy, and the sustenance of transport is heavily dependent on commercial vehicles running on heavy-duty diesel engines. The significant difference in the performance of all types of heavy-duty commercial diesel engines requires specific heavy-duty motor oils (HDMO) composed according to the recommendations of the original equipment manufacturer (OEM).

Today, all heavy-duty motor oils are formulated based on specific requirements and original equipment manufacturer (OEM) guidelines. These norms ensure the engine oil performs in the best possible way to enhance the engine’s performance, durability and efficiency. Here, we will be discussing the guidelines followed while formulating and assigning an HDMO for a commercial diesel engine:

What are original equipment manufacturer guidelines?

The original equipment manufacturer guidelines, or simply called OEM guidelines, are specifications set by a commercial diesel engine manufacturer for its engine(s) to operate at its supposing performance, operate reliably and perform efficiently from it. The following are the aspects which the OEM guidelines for an engine oil cover:

• Viscosity grade
• Type of oil
• Performance standards
• Drain intervals

Purpose of Following OEM guidelines

Under OEM guidelines, an engine performs optimally under a wide range of temperatures, climatic conditions and loads. The following are some reasons why you should go for an engine oil matching the OEM guidelines:

Enhanced Performance

The right engine oil ensures the lubricant to provide protection and excellent thermal and oxidative stability. It reduces wear rate and sludge formation and enable for longer engine life resulting in lowering total cost of ownership.

Dedicated Lubrication

Heavy Duty Engine OEM will recommend different type of fluids and greases across its vehicles to ensures optimal sync in the performance of all moving components – either working within a single ecosystem or separately in different sections of a powertrain.

Warranty Period

Using OEM-approved engine oils or grades ensures that the warranty offered on cycle parts by the manufacturer remains intact, which is handy in the event of a mechanical fault during warranty period.

Compliance with Emission Regulations

Engine manufacturers recommend specific engine oil or minimum specification requirement to comply with the latest emission regulation requirements. Using lubricants that are not recommended can impact efficiency of exhaust after treatment system, such as diesel oxidation catalyst (DOC), Selective Catalytic Reduction (SCR) and Diesel Particulate Filter (DPF).

Parameters Considered in an OEM Guide for an Engine Oil

Viscosity Grade

The lubricants recommended by commercial vehicle manufacturers in India usually specify viscosity grades based on SAE J300 standards. Vehicle manufacturers in India generally recommend SAE 15W-40 and SAE 10W-30 viscosity grade engine oils, with the latter recommendation for its versatility across a range of climate temperatures and provides fuel efficiency.

Performance Standards

Commercial vehicle manufacturers in India typically recommends API category of API CK-4, CJ-4, and CI-4+, with some manufacturers also recommend ACEA E4, ACEA E7, ACEA E8, ACEA E11 and BIS-certified grades.

Compatibility with Emission Systems

After the transition to BS VI emission norms, HDMOs with low SAPS (Sulphated Ash, Phosphorus, Sulphur) content are recommended for commercial diesel engines. An engine oil with low SAPS protects the emission system components, such as SCR and DPF.

Drain Interval

It is the time or kilometre interval between two oil change schedules. All HDMOs have their own specified drain intervals, with the majority of commercial vehicles in India having drain intervals of 40,000 to 80,000 km.

Things to Look for While Selecting the Right HDMO Using OEM Guidelines

While selecting a heavy-duty motor oil for your commercial vehicle diesel engine, keep an eye on the following pointers:

• OEM guidelines for the engine and service schedules for the engine mentioned in the owner’s manual
• OEM approval on the engine oil label or datasheet
• Viscosity grade – prefer SAE 10W-30 for colder northern regions of India and SAE 10W-30 or SAE 15W-40 for other parts of the country
• Recommended industry specification such as API, JASO or ACEA performance level
• Compatibility with BS6 emission norms, especially for modern BS6 diesel engines

Did not comply with these recommendations may lead to a faster wear rate of the engine, increased sludge formation, damage to DPF and SCR, and a higher frequency of oil changes.

Conclusion

There’s more to selecting the right heavy-duty motor oil for your commercial vehicle diesel engine than just the viscosity. High-quality motor oils formulated with premium base oil, advance additives and formulation experiences capable to comply with industry and OEM specification ensure the best possible performance, efficiency and compliance with emission regulation requirements, even in the challenging climatic and road conditions of India.

FAQs

What is OEM-approved oil?

Original Equipment Manufacturer (OEM)-approved engine oils for commercial vehicle diesel engines are heavy-duty motor oils formulated according to the specifications set by the engine manufacturer, thus improving performance, reliability and efficiency of the engine. These specifications include viscosity grade, performance standards, type of oil and drain intervals.  

What are the guidelines for oil consumption?

In India, the guidelines for oil consumption in commercial vehicles with diesel engines depend on OEM recommendation according to OEM manual or maintenance programs by the owners.

How to select the oil grade?

For engine oil’s viscosity grade, preferable SAE  10W-30 for colder northern regions of India and SAE 10W-30 or SAE 15W-40 for other parts of the country.