Engines

Detroit's mainstream long-haul engine, standard in most Freightliner Cascadias. It is the most common engine on the road in North America, simply because of Cascadia volume.

The smaller DD13 (370–525 hp) is Detroit's other Cascadia option. It is lighter for better payload, at the cost of some low-end torque compared with the DD15.

PACCAR's engine for both the Peterbilt 579 and Kenworth T680 — the same engine, badged for both brands.

A CARB-compliant variant is offered at 455 hp/1,650 lb-ft or 510 hp/1,850 lb-ft just for California operation.

Cummins' flagship heavy-duty engine. It is available across several OEM chassis (including as an option in the Freightliner Cascadia). It has the widest availability of any engine brand since it isn't tied to one truck maker.

Cummins sells the X15 in three tuned series (Efficiency, Performance, Productivity) for the same base engine. The right one depends on whether you're tuning for fuel economy, pulling power, or a heavy-haul duty cycle.

Volvo's only engine offering in the VNL. It comes in standard variable-geometry turbo or turbo-compound setups.

The turbo-compound version recovers extra energy from exhaust gas to boost efficiency. It's the version paired with the higher torque ratings.

Mack's mainstream on-highway engine for the Anthem. It is also offered in the fuel-efficiency-focused MP8HE variant.

The MP8HE trades some peak horsepower for turbo-compounding. Mack's own literature markets it at around a 3% fuel efficiency gain over the standard MP8.

International's engine, sold only as part of the S13 Integrated Powertrain. It isn't a standalone engine option. It isn't offered apart from the T14 transmission.

It's sold as an integrated unit with the T14 transmission. So you can't mix an S13 with a different transmission brand the way you sometimes can with other OEM engines.

Detroit's smaller engine. It is offered in the Freightliner Cascadia, M2 112 Plus and 114SD Plus, and the Western Star 47X and 49X.

The DD15 is the larger Detroit option. The DD13 guide says which figures come from Detroit's North American pages and which come from its Australia and New Zealand sheets.

Detroit's largest on-highway engine, built for heavy loads. Detroit's page lists it for the Freightliner Cascadia and the Western Star 49X.

Detroit lists turbo compounding on the DD16 to turn exhaust heat into extra power. Match the rating to your gross weight.

PACCAR's smaller engine. PACCAR says it weighs 300 lb less than a 13-liter engine.

PACCAR's 2024 sheet lists the same oil intervals and warranty terms as the MX-13. The rating you need is the main difference.

Cummins' 11.8-liter engine, smaller than the X15. Cummins sells it in the Freightliner Cascadia and in vocational trucks from several makers.

Some X12 engines were part of a 2021 fuel tube recall. The X12 guide has the details.