Engines and Drive Systems
By Maggie MacHale
Rethinking Power
Diesel, hydrogen and what’ s next for off-highway power
In today’ s industry demands, engine and drive systems are asked to offer reduced emissions, fuel flexibility and lower total cost of ownership, all while providing more reliable, higher performance. In response, manufacturers in off-highway sectors, including cranes, lifting equipment and heavy construction machinery, are advancing both traditional diesel platforms as well as alternative fuel technologies.
These new engine products are able to achieve greater fuel efficiency, lower emissions compliance, longer maintenance intervals, improved durability within demanding applications and renewable fuel readiness.
Diesel Still Dominates
The Cummins Next Gen X15, Caterpillar C32B and Liebherr D9612 serve as indicators that diesel remains a prominent figure in the off-highway engine market, but also that there is a significant shift toward improving efficiency.
The Cummins Next Gen
2027 X15 Off-Highway engine made its debut at CONEXPO-CON / AGG 2026 in Las Vegas, Nevada. This version, updated from the 2024 X15, runs primarily on diesel, but is also compatible with a range of alternative fuel options, including HVO biofuels and future hydrogen capabilities. It also has a 4 % improvement in fuel efficiency compared to the 2024 EPA X15.
The engine incorporates several engineering updates aimed at improving performance and efficiency. Weight has been reduced while strength has been increased through a redesigned, sculpted engine block, resulting in a weight-neutral configuration. An updated piston bowl design raises the compression ratio, while a revised piston skirt reduces friction to improve fuel economy. The selective catalytic reduction
( SCR) system has also been enhanced to improve NOx conversion and cold-temperature performance. In addition, a 48-volt alternator supports electric heating technology for faster catalyst warmup and provides dedicated power for the system’ s thermal management needs.
In the design, several elements are also intended to improve
The Cummins Next Gen X15 has a 4 % improvement in fuel efficiency compared to the 2024 EPA X15.
The Cat C32B features an updated engine block, revised lubrication systems and an induction-hardened crankshaft.
maintenance and operating costs, such as cartridge-style filters that reduce service complexity while minimizing environmental impact. Extended maintenance intervals further help reduce downtime, supporting longer service life between scheduled maintenance events.
Introduced in September 2025, the Caterpillar C32B for large off-highway machines, such as cranes, large loaders, hydraulic power units, dredgers and surface hauling equipment, is a 32.1-liter, 12-cylinder engine. This introduction focuses on durability and rebuild intervals, supported by structural enhancements designed to improve long-term reliability under heavy-duty operating conditions.
Updates to the engine include a strengthened cast-iron engine block, an induction-hardened crankshaft with larger journal diameters and increased bearing area and a revised lubrication system with a higher-capacity oil pump and improved cooling flow. Additional refinements to the cylinder head and sealing
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July 2026 • www. cranehotline. com