• Advanced Air Handling – Electronic control for precise air handling.
• Proven Wastegate Turbocharger – A small-frame, fixed geometry, waste gate-style turbocharger is used. A watercooled bearing housing adds durability.
• Engine Control Module (ECM) – Constantly monitors and controls engine sensors, fuel system and ignition system. Drive-by-wire throttle control. Provides OEM and end users with the ability to tailor performance of the engine to fit the vehicle’s mission. Full interface capability to Cummins INSITE™ and Cummins QuickCheck diagnostic service tools.
• High-Energy Ignition System – Provides better performance and longer service intervals, improved spark plug and coil durability and self-diagnostics. The ignition module and fuel module are controlled by a full-authority CM2180A ECM with programmable features, which is compatible with Cummins diagnostic tools.
• Accessory Belt Drive System – Self-tensioning serpentine polyvee belt accessory drive system for water pump, engine-mounted fan hub and most alternators.
• Air Intake System – Charge-air cooling reduces emissions by lowering intake manifold air temperatures.
• High-Efficiency Lube Cooler – Lowers oil temperatures, for longer engine life.
• Crankshaft – The eight-counterweight, fully balanced, high-tensile-strength steel forging has induction-hardened fillets and journals, for outstanding durability.
• Optional Engine Braking – 240 hp (180 kW) at 2100 rpm.
• Transmission – Automatic and manual options available.
• Front- and Rear Engine Power Take-Off (FEPTO and REPTO) – Options provide additional torque, for a variety of vocational applications.

ISX12 G Torque Curves

With torque curves similar to those of the ISX12 diesel within the 1150 lb-ft-to-1450 lb-ft (1559-1966 N•m) range, the ISX12 G offers comparable vehicle performance and drivability.

Gearing Recommendations
For best reliability and durability, the recommended maximum GVW for the ISX12 G in line-haul applications is 80,000 lbs (36,287 kg). Recommended gearing for line-haul applications is 1400 rpm to 1475 rpm at cruise speed for optimum fuel economy or 1450 rpm to 1500 rpm at cruise speed for a balance of fuel economy and performance. For vocational applications, gearing recommendations are 1450 rpm to 1600 rpm at cruise speed for fuel economy or 1550 rpm to 1700 rpm at cruise speed for a balance of fuel economy and performance.

Optimizing Performance with PowerSpec
Cummins PowerSpec helps you find the ideal gearing specs for engine performance or fuel economy, making it possible to tailor the operation of Cummins Westport engines to fit every customer’s application. PowerSpec can also read fault codes, and can be programmed to collect trip information for multiple drivers. PowerSpec works on both the ISL G and the ISX12 G. 

Base Warranty
The automotive base warranty for the Cummins Westport ISX12 G natural gas engine is the same as for the Cummins diesel base platform. Base warranty covers 2 years/250,000 miles (402,336 km) and 100 percent parts and labor on warrantable failures.*

Extended Coverage
For additional peace of mind, Cummins Westport offers a variety of extended coverage plans to meet every customer’s need. For details on extended coverage options, contact your local Cummins distributor or Cummins Westport representative.

Better Customer Care
Cummins Westport-powered vehicles are supported by Cummins service network, the largest and most capable in North America. Cummins authorized technicians are fully trained on Cummins Westport natural gas engines, with ready access to Genuine Cummins Parts and warranty support. For questions regarding your Cummins Westport engine, or for assistance in finding a repair facility in the United States or Canada, call Cummins Care at 1-800-CUMMINS.

Cummins Westport – The Natural Choice
Cummins Westport Inc. designs, engineers and markets 6- to 12-liter spark-ignited natural gas engines for commercial transportation applications such as trucks and buses. Our dedicated 100 percent natural gas engines are manufactured by Cummins, and are available as a factory-direct option from leading truck and bus manufacturers.

To learn more about Cummins Westport and natural gas as a transportation fuel, visit the Cummins Westport Natural Gas Academy for information, resources, videos and more – at cumminswestport.com/natural-gas-academy.