As we head toward spring and start to leave the colder winter months behind us, it’s important to reflect on the climates and temperatures that your fleet operates in. Many trucks across North America will experience a range of both winter and summer temperatures – from mild and temperate, to extremes of both hot and cold.

But what impact do extreme seasonal temperature changes have on the performance of a heavy-duty engine lubricant? And what do fleet managers need to be aware of when they select an engine oil?

The Role of Engine Oils

Heavy-duty engine oils play a crucial role in engine performance and efficiency. Protecting the internal components of the engine’s hardware, a quality lubricant can help prevent engine wear and unplanned maintenance.

By minimizing metal-to-metal contact between moving components and decreasing pumping and rotational losses, reductions in fuel consumption and emissions can also be achieved.

The industry journey toward lower viscosity lubricants has contributed to efficiency gains, by offering lower frictional resistance and drag within the engine. This means that the lubricant can flow more freely around the engine and that it does not have to work as hard to provide the same level of power.

However, when selecting an engine oil, it’s important to consider the fleet’s operating conditions, as each lubricant has a temperature range for optimal performance, which is denoted by its SAE viscosity grade.

Indicating viscosity at both low and high temperatures, the SAE grade of the oil is a vital factor in determining an engine oil’s ability to perform in certain environments, as it is directly affected by temperature.

Extreme Winter Temperatures

In cold environments, the lubricant can take longer to warm up and if temperatures drop into the ‘critical’ zone of the engine oil’s operating range, the oil can stiffen or become overly viscous. Not only can this delay the lubrication of engine hardware, but if oil flow is negatively impacted, the engine could seize or in worse case scenarios, fail.

For fleets operating in cold environments or extreme winter conditions, selecting a lubricant that will maintain its flow is crucial. This will help maintain the lubrication of internal components and adequate flow around the engine.

The Original Equipment Manufacturer (OEM) manual should always be consulted for fleets operating in cold environments as it will provide guidance on the lowest viscosity grades accepted by ambient temperature requirements.

A lower viscosity lubricant will be able to flow more freely around the engine and enable the engine to operate with improved efficiency, even in colder temperatures.

Looking Ahead to Summer

As we head toward the warmer summer months, it’s important to also be aware of the challenges that hot temperature environments can present for engine oils and the lubricant technology that helps fleets continue to run smoothly.

In extreme hot temperatures, a decrease in the lubricant viscosity can reduce the thickness of the lubricant film.  Not only can this compromise the protection of the engine, but it can also result in accelerated engine wear and overheating.

When selecting an engine oil for operation in warmer environments, higher viscosity oils can be considered. OEM recommendations may include ambient temperature summaries and should be the starting point to selection of the appropriate viscosity grade.

It’s also important to consider the impact of oil volatility, as the hotter the temperature becomes, the more volatile the oil can become. For this reason, a low volatility lubricant is an effective solution for hotter environments.

The type of engine oil should also be a key factor in selection of any engine oil, but particularly for those operating in hot climates. There are three types of engine lubricant, full synthetic, synthetic blend and conventional.

Full synthetic and synthetic blend engine oils offer better stability than non-synthetic oils and benefit from improved performance in varied weather conditions. This means that they can withstand temperature changes better than their conventional counterparts and offer adequate lubrication throughout the year. Synthetic oils also benefit from performance enhancing additives to provide greater levels of performance.

A Multigrade Solution

For all year and all-season protection, a multigrade heavy-duty lubricant the industry best practice solution. For example, SAE 10W-30 are effective lubricants for fleets that work in extreme climates.

Multigrade lubricants have helped the industry move forward over the years – reducing the need for seasonal changeouts and incorporating modern lubricant technologies that enable better lubrication and in turn, improve engine performance and help reduce unplanned maintenance.

However, as with all lubricant selections or changes, the first step should always be to consult the OEM manual and a lubricant expert who can provide insight and advice based on your fleet’s specific operating conditions and requirements.

Climate and seasonal change can have a significant impact on the condition of an engine lubricant, and in turn its ability to adequately protect vital engine components. By selecting a multigrade engine oil, fleets can benefit from reduced engine wear and unplanned maintenance, and importantly, a lower total cost of ownership throughout all four seasons.

About the Author: Darryl Purificati is the senior technical advisor, OEM/Automotive, at HF Sinclair. This article was authored and edited according to WT editorial standards and style to provide useful information to our readers. Opinions expressed may not reflect that of WT.