Mack Trucks used ACT Expo to spotlight its new EPA 2027-compliant MP13 engine, positioning it as the cornerstone of a broader overhaul of its Class 8 lineup.

The 13-liter engine delivers up to 540 hp and 1,950 lb.-ft. of torque, while improving fuel efficiency by as much as 3% compared to the previous MP13, the company said. It also offers more than 20% greater braking performance, reaching up to 630 braking horsepower.

“The MP13 represents years of engineering work to deliver an engine that meets the toughest emissions standards in our industry’s history, but does so without asking our customers to compromise on power or efficiency,” said Jonathan Randall, president of Mack Trucks North America.

The engine meets EPA 2027 emissions standards through a combination of in-cylinder improvements and aftertreatment upgrades designed to reduce nitrogen oxide (NOx), particulate matter and CO2 emissions.

Built for performance and compliance

Mack executives said the MP13 was engineered to balance regulatory compliance with real-world performance — a key concern for fleets preparing for EPA27.

The engine features an optimized torque curve that delivers peak torque at just 900 rpm, supporting downspeeding and improved drivability. It also incorporates a more efficient turbocharger and predictive software designed to smooth engine response.

Fuel flexibility is another focus. The MP13 is compatible with renewable diesel (R100) and biodiesel blends up to B20, expanding options for fleets looking to lower carbon intensity without moving away from diesel platforms.

An updated mDRIVE automated manual transmission has also been paired with the engine, improving communication between engine and transmission for quicker, smoother shifts.

Part of a broader product reset

The MP13 arrives as Mack completes a sweeping renewal of its conventional truck lineup, a process that has unfolded over the past year.

The rollout began with the Pioneer, followed by the all-new Anthem. More recently, Mack introduced a redesigned Granite vocational truck and the Keystone on/off-highway model, giving the OEM a fully refreshed Class 8 portfolio.

“These four trucks are the combination of a massive R&D investment and over eight years of extensive work,” company executives said during the press event.

The updated lineup integrates a range of new technologies, including advanced driver assistance systems, digital mirrors, 360-degree camera views for vocational applications, and expanded connectivity for diagnostics and uptime.

Driver comfort has also been a focus, with redesigned seating systems offering heating, ventilation and massage functions, along with ergonomic improvements aimed at longhaul applications.

Multiple applications, no trade-offs

The EPA27-compliant MP13 will be available across Mack’s highway and vocational lineup.

In the Pioneer and Anthem, it targets long-haul efficiency. In the Granite, it brings fuel savings to vocational applications, while in the Keystone it is expected to deliver up to 6% improved fuel efficiency compared to the Pinnacle.

Executives stressed that meeting stricter emissions standards did not come at the expense of performance or durability.

“We haven’t compromised on anything in terms of performance or maintenance,” Govi Kannan, DVP global product owner, said during a Q&A session, adding expectations are for improved overall performance.

Orders open this summer

Mack said the EPA27 MP13 will be available to order starting in August 2026, with production aligned to model year 2028 trucks.

The company also reiterated it will continue to offer a range of powertrain options, including battery-electric and natural gas models, alongside its advanced diesel platform.