The Cat® C4.4 ACERT™ Industrial Power Unit is offered in ratings ranging from 74.5-129.4 bkW (100-173.5 bhp) @ 2200 rpm, which meet U.S. EPA Tier 4 Final, EU Stage IV emission standards. Tier 4 Interim Equivalent and Stage IIIB Equivalent ratings are also available using Flex options. Conveniently pre-configured for a wide range of applications, the Cat® Industrial Power Unit is a complete power package containing a radiator, flywheel, alternator and alternator wiring completely pre-assembled for fast, straightforward installation in a number of OEM, customer and packager applications. These fuel efficient units are ready made for irrigation, industrial, mining and other pump applications.

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Power Rating
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Maximum Power 173.5 HP 129.4 kW
Maximum Torque 553.2 lb-ft @ 1400 rpm 750.0 Nm @ 1400 rpm
Rated Speed 2200 rpm 2200 rpm
Minimum Power 100.0 HP 74.5 kW

Reliable, Quiet and Durable Power

World-class manufacturing capability and processes coupled with proven core engine designs assure reliability, quiet operation, and many hours of productive life.

High Performance

Series turbocharging with smart wastegate available on specific ratings for fast response, high power, and increased torque.

Fuel Efficiency

Fuel consumption optimized to match operating cycles of a wide range of equipment and applications while maintaining low operating costs.

Fuel & Oil

Tier 4 Interim or Tier 4 Final, Stage IIIB or Stage IV engines require Ultra Low Sulfur Diesel (ULSD) fuel containing a maximum of 15 ppm sulfur, and new oil formulations to support the new technology. Cat® engines are designed to accommodate B20 biofuel. Your Cat dealer can provide more information regarding fuel and oil.

Broad Application Range

Industry leading range of factory configurable ratings and options for agricultural, material handling, construction, mining, aircraft ground support, and other industrial applications.

Package Size

Ideal for equipment with narrow engine compartments. Multiple installation options minimize total package size.

World-class Product Support Offered Through Global Cat Dealer Network

  • Scheduled maintenance, including SOSSM sample
  • Customer Support Agreements (CSA)
  • Caterpillar Extended Service Coverage (ESC)
  • Superior dealer service network
  • Extended dealer service network through the Cat Industrial Service Distributor (ISD) program

Tier 4 Final, Stage IV Aftertreatment Features


Regeneration. The DOC/SCR modular design offers a simple, compact package while providing high levels of performance. A DOC/DPF/SCR option is available for higher power machines. While in use, both DOC/SCR an DOC/DPF/SCR systems offer transparent operation to the user.


Mounting. Extensive range of inlets and outlets, as well as remote and on-engine installations, provide flexibility for many installations.
Service. Both DOC/SCR an DOC/DPF/SCR systems are service-free for the emissions life of the engine.

C4.4 Standard Equipment

Air Inlet System
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  • Standard air cleaners