The heavy-duty trucking industry is increasingly focused on improving sustainability. One area fleet manager can target is using eco-friendly engine oils made from renewable sources with lower emissions impacts. Here are some of the options when selecting greener, more sustainable oil formulations.

Renewable Base Oils

Conventional engine oils use non-renewable Group I to III base oils derived from crude oil. Renewable oils made from plant-based sources provide a more sustainable alternative. These include:

• Soybean oil – Made from soybeans, domestic and renewable. Offers good cold flow properties.
• Canola oil – Derived from canola, with excellent stability. Ideal for biodiesel fuelled engines.
• Palm oil – Made from palm plants. However, large plantations for production raise environmental concerns.
• Algae oil – Futuristic oils from algae sources are still under development but show sustainability promise.
• Waste cooking oils – Recycled and filtered waste oils from restaurants make affordable re-refined base oils.

Synthetic base oils derived from natural gas feedstocks are another domestic and stable option. The right formulation is key as plant-based oils can have drawbacks like oxidative and thermal instability.

Lower Emission Oils

Conventional oils use petroleum-based additives containing sulphur, phosphorus, and metals associated with emissions and pollution. “Low SAPS” oils feature “green” additives with:

• Lower sulphur and sulphated ash
• Reduced phosphorus
• Little or no heavy metals

This helps combat sulphur oxide particulates, ash deposits, and oil breakdown in emission-controlled engines. Less metallic additives also make used oil recycling simpler.

Extended Drain Intervals

Synthetic oils and newer conventional allow extended drain intervals upwards of 35,000+ miles versus traditional 15,000-mile changes. Sinopec noted that less frequent oil changes mean using less oil over time – reducing consumption, waste, and change costs. Oil analysis helps safely maximize intervals.

Re-Refined Base Oils

The use of recycled motor oil to produce Group I base oils reduces waste while creating less expensive, domestic supply. Chemically re-refining used oil enables solo use or blending with virgin oils. However, performance is not quite on par with non-re-refined.

Biodiesel Use

For fleets using biodiesel blends, “biodiesel-capable” oils withstand the increased oxidation and acid formation stemming from biodiesel combustion. This prevents premature breakdown while enabling sustainable biofuel use.

Emissions Compliance

Look for oils meeting the latest API CK-4 and FA-4 ratings designed for emission-controlled diesel engines with exhaust aftertreatment. These oils produce less particulate matter and other emissions.

The Green Lubricant Standard

Oils certified to meet the US EPA’s Environmentally Acceptable Lubricant standards are biodegradable, non-toxic, and derived from renewable sources. This denotes compliance as sustainable lubricants.

Soybean Oil Based Lubricants

Soybean oil has emerged as a promising renewable and domestic feedstock for eco-friendly engine oils. Here is an overview of using soybean oil in heavy duty truck lubricants:

• Soybeans as Feedstock – Soybean oil is derived from pressing and solvent extracting oil from soybeans. The US produces over 90% of global output, making it a stable domestic source.
• Refining Process – Soybean oil consists mainly of triglycerides. Refining steps like degumming, neutralization, bleaching, and deodorizing remove impurities to produce a stable base oil.
• Key Properties – Soybean oils offer good viscosity indexes, oxidation stability and low temperature flow characteristics on par with Group II petroleum oils.
• Formulation Design – Additive packages combat soybean oil’s drawbacks like thermal breakdown and high saturated fat content for optimal finished oil performance.
• Oxidation Resistance – Antioxidants and synthetic base oil blending counteracts soybean oil’s lower oxidation resistance compared to petroleum.
• Emissions Reduction – Soybean-based oils can reduce sulphur oxide, CO, and particulate matter emissions compared to conventional oils.
• Biodegradability – Soy-based lubricants biodegrade rapidly versus petroleum oils, reducing environmental impacts of spills or leakage.
• Cold Flow – While flow is improved over traditional oils, soybean oils fall short of synthetics in cold weather performance. Pour point depressants help.
• Alternative Fuel Use – Soybean oils offer compatible lubrication for biodiesel fuelled engines. Canola oil also sees use in this application.
• Adoption Challenges – Performance shortcomings, supply chain factors and pricing hinder widespread soybean oil adoption currently. Fleets use blends.
• Sustainability Factor – Domestic production and renewability make food grade soybean oil more eco-friendly than petroleum-based oils.

Soybean oil lubricants offer promise but also trade-offs versus conventional oils. As formulations continue to evolve, expect growing adoption in tandem with expanded sustainable fuel use.

Canola Oil as a Base Oil

Like soybean oil, canola oil is also being evaluated as a renewable base oil for engine lubricants:

• Canola Plants – Canola refers to cultivars of rapeseed bred specifically for oil food production in cooler climates. Canada leads global canola oil output.
• Refining Process – Steps like caustic refining, bleaching, and deodorization process canola oil by removing impurities and odours.
• Properties – Canola offers good viscosity index, oxidation stability, and cold flow properties comparable to premium petroleum oils.
• Stability Factor – Of all vegetable oils, canola oil exhibits excellent thermal and oxidative stability for sustained lubricant life.
• Emissions Reduction – Canola oil produces less VOC, CO, and particulate emissions than conventional lubricants.
• Biodiesel Engine Use – High stability suits canola oil for engines running biodiesel fuel blends which accelerate oxidation.
• Biodegradability – Like other vegetable oils, canola lubricants biodegrade rapidly to minimize environmental impacts.
• Cold Flow – Solidification temperature of canola oil is below -30°C, enabling good low temperature pumpability.
• Limitations – Canola oil supply and costs currently limit widespread use. It works well in blends with petroleum base oils.
• Sustainability – Domestically grown, renewable canola oil offers a reduced environmental footprint versus petroleum oil sources.

Canola shows promise as an eco-friendly and high performing base stock for diesel engine oils. Improved low temperature flow gives it an edge over soybean oil in colder regions. Look for wider adoption as supply expands.

Final words

While engine oil is a minor operational cost, proactive fleets can integrate sustainable offerings into lubrication programs. Using renewable, recycled, or extended life oils reduces environmental impacts one oil change at a time. Specifying green lubricants demonstrates corporate responsibility and environmental stewardship. With emerging technologies and processes, expect the lineup of eco-conscious truck oils to continually evolve in line with legislative standards and consumer demand.