Volvo, Mack unveil EPA 2027-compliant heavy-duty diesel engines
8 May 2026
Volvo Trucks North America has unveiled its US EPA 2027-compliant D13 heavy-duty engine, while Mack Trucks—a Volvo subsidiary—has introduced the 2027 Mack® MP13 engine. Both engines were showcased at the Advanced Clean Transportation (ACT) Expo held on May 4-7 in Las Vegas, Nevada.
The new D13/MP13 engines deliver up to 540 hp and 1,950 lb-ft (2,644 Nm) of torque, while providing up to 3% improved fuel efficiency compared with the previous engines, according to Mack Trucks. In addition, they deliver stronger engine braking power of up to 630 hp—more than 20% improvement over its prior iteration—to provide stronger downhill control and improved drivability for heavy loads and steep grades.
The engines are integrated with the respective Volvo I‑Shift and Mack mDRIVE™ automated transmissions.
The D13/MP13 engines meet the EPA 2027 emission standards through several engine improvements combined with an electrically heated aftertreatment system. The engines utilize two electric heaters—one located before the DOC/DPF and another before the SCR catalyst. The heaters are powered by a dedicated 48-volt alternator, while other engine and vehicle systems are powered by a 24-volt alternator.
Changes to the 2027 D13/MP13 engines include:
- Redesigned, more efficient turbocharger, with a pre-turbine throttle
- Optimized torque curve that delivers peak torque at just 900 rpm, supporting downspeeding and improved drivability
- Compression ratio increased from 18:1 to 20:1
- 14-wave pistons (Volvo introduced a seven-wave piston in 2024, compared with six waves previously)
- Closed crankcase ventilation
The D13/MP13 engines are compatible with renewable diesel (R100) and biodiesel blends up to B20—up from B10 in the previous engines.
The 2027 D13/MP13 engines will be available for order beginning in August 2026, with production timed to model year 2028 vehicles. The engines will be available across the respective Volvo and Mack highway and vocational truck lineups.
International Motors, Daimler Truck, and Cummins announced their EPA 2027-compliant engines earlier this year. To meet the emission standards, Cummins will use the same approach as Volvo—two electric heaters in the aftertreatment system—while International and Daimler will use light-off SCR catalysts, with no electric heating.
Source: Volvo Trucks | Mack Trucks