State of the industry
The heavy-duty (HD) emissions landscape is changing. With the U.S. Environmental Protection Agency (EPA) rolling out stringent emissions regulations for HD trucks – starting with model year 2027—fleets are facing strict reductions in nitrogen oxide and diesel particular matter (PM) emissions, and a greater focus on extending the service life of components like diesel particulate filters (DPFs), moving from 435,000 to 650,000 miles (EPA.gov). These standards, paired with California’s equally stringent CARB rules, are transforming modern vehicle and engine design, making fleet readiness more important than ever.
Enter PC-12: Next-gen engine oils for new-gen vehicles
To support these advances, the API is developing Proposed Category 12 or PC-12 – a next-generation engine oil standard set to debut in early 2027. PC-12 is being created to meet modern engines and aftertreatment requirements through:
- Lower viscosity grades (SAE XW-20) to reduce friction, improve fuel economy, and cut greenhouse gas (GHG) output
- Tighter limits for phosphorus, sulfur, and sulphated ash to protect aftertreatment system hardware, contributing to their extended lifespan
- Two distinct subcategories – aligning with the viscosity divide that exists today with API CK-4 and FA-4:
- PC-12A, designed for compatibility with older engines
- PC-12B, optimized for the latest engine designs
Much work is being completed to keep PC-12 on track of the desired First Licensed date of January 1, 2027.
Switching to Low-Viscosity Oils
Even before PC-12 rolls out, low-viscosity oils are already delivering measurable benefits without compromising the durability of engine life or the compatibility of the emissions systems. These additives are designed to ensure lubricants can function at much lower viscosities and retain their protective properties event when properly extending draining intervals. Advantages from switching your fleet to lower viscosity oils include:
- Meaningful cost savings. A commercial truck can easily consume more than $70,000
(20,500 gallons) of diesel fuel per year. A switch from 15W-40 to a properly formulated 10W-30 can result in up to 3% fuel savings through reducing friction and maintaining outstanding oxidation performance (where OEM recommended). - Improved engine durability, extended engine life, performance, and protection in old and newer engines.
- Flexible formulation for heavy, medium, and light-duty off-road and commercial on-road vehicles, as well as stationary diesel engines.
- Most products are approved or suitable for use in engines by leading heavy-duty engine manufacturers, including Ford, Paccar, Volvo, Caterpillar, Cummins, Mack, Detroit Diesel, and Mercedes-Benz.
- Multiple options, such as API CK-4 and FA-4 engine oils to fit your unique fleet and HD operations.
Some HDEOs are guaranteed to reduce total operating costs, improve fuel efficiency, and improve carbon footprint (Citgo guarantees all of its lubricants). This results in less downtime and more operating hours.
A balanced formula of calcium and magnesium may be a way to reduce carbon emissions while enhancing engine performance
Choosing a heavy-duty engine oil (HDEO) that delivers the performance needed for newer engine designs while improving performance in older engines is key. Oils with SAE 10W-30 viscosity grade help operators attain new efficiency standards by improving fuel economy and providing superior engine durability.
Citgo Citgard 700 Synthetic Blend Heavy-duty Engine Oil SAE 10W-30 has among the highest TBN and TBN retention performance in the industry, protecting against acid accumulation.
Premium API CK-4 heavy-duty engine oils like Citgo CitgardD 700 Synthetic Blend
Heavy Duty Engine Oil SAE 10W-30 utilizes a balanced approach to protect your engine and maintain your DPF life through total base number (TBN) and a balanced detergent package, excellent oxidation control, and impressive wear performance.
What sets this engine oil apart is its thoughtfully engineered detergent additive package. Unlike many competitors that rely exclusively on calcium detergents, Citgard 700 Synthetic Blend Heavy Duty Engine Oil SAE 10W-30 combines both calcium and magnesium detergents in a carefully balanced formulation.
This combination delivers significant advantages, including:
- Reduced exhaust flow resistance
- Reduced back pressure (50%)
- Less workload on the engine
- Improved fuel efficiency
In a field trial, Citgard 700 Synthetic blend 10W-30 tested at a 2.1% fuel efficiency savings versus a 15W-40 for the new oil, and after 50,000 miles, the Citgard 700 10W-30 still showed a 1.8% fuel efficiency savings.
Citgo Citgard 700 Synthetic Blend Heavy Duty Engine Oil SAE 10W-30 has a successful
history with some of the largest fleets in the nation, including J.B. Hunt, Crete Carrier
Corporation and Brundage Bone Concrete Pumping.
Switch today, profit now
Shifting to low-viscosity engine oils will help fleets lower operational costs, enhance engine reliability, and comply with tightening emissions regulations. As the PC-12 era approaches, embracing these formulation upgrades ahead of the curve will deliver cost savings, uptime, and environmental compliance.
Contact your supplier about choosing the right balanced formula for heavy-duty engine oils, such as the premium line of Citgo Citgard Heavy Duty Engine Oils, for your fleet operation and emissions compliance. The right HDEO could also help you streamline and simplify your inventory planning and supply needs.