ISX12N

The 2018 ISX12N continues the evolution of emission leading natural gas engines from Cummins Westport, with the lowest certified Ultra Low NOx emission engines in North America – 90% lower than current North American EPA standards. With 400 hp / 1,450 lb-ft torque, and near-zero emissions, the ISX12N is well suited for heavy-duty regional-haul truck, vocational, and refuse applications, and motorcoach.

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NOx emission 0.02 g / bhp-hr. (90% below EPA)
Maximum Horsepower 400 HP | 298 kW
Peak Torque 1,450 LB-FT | 1,966 Nm
Governed Speed 2100 RPM
Type 4-cycle, spark-ignited, in-line
6 cylinder, turbocharged, CAC
Engine Displacement 762.2 CU IN | 11.9 LITERS
Number of Cylinders 6
Operating Cycles 4
Net Weight (dry) 2,650 lb | 1,202 KG
Fuel Type CNG / LNG / RNG
Aftertreatment Three-Way Catalyst
Base Warranty 2 Years, 250,000 Miles
(402,336 KM)
Engine Model Advertised Horsepower
(kW) @ rpm
Peak Torque 
lb-ft (N•m) @ rpm
Governed
Speed
Line Haul / Regional Haul Truck and Vocational      
ISX12N 320 320 (239) @1700  1150 (1559) @ 1200 2100 rpm
ISX12N 330 330 (246) @ 1700 1250 (1695) @ 1200 2100 rpm
ISX12N 350 350 (261) @ 1700 1450 (1966) @ 1200 2100 rpm
ISX12N 385  385 (287) @ 1700 1350 (1830) @ 1200 2100 rpm
ISX12N 400 400 (298) @ 1800 1450 (1966) @ 1200 2100 rpm
Commuter Coach      
ISX12N 400 400 (298) @ 1800 1450 (1966) @ 1200 2100 rpm
Motorcoach      
ISX12N 320 320 (239) @1700  1150 (1559) @ 1200 2100 rpm
ISX12N 330 330 (246) @ 1700 1250 (1695) @ 1200 2100 rpm
ISX12N 350 350 (261) @ 1700 1450 (1966) @ 1200 2100 rpm
ISX12N 385  385 (287) @ 1700 1350 (1830) @ 1200 2100 rpm
ISX12N 400 400 (298) @ 1800 1450 (1966) @ 1200 2100 rpm
Refuse      
ISX12N 320 320 (239) @ 1700  1150 (1559) @ 1200 2100 rpm
ISX12N 330 330 (246) @ 1700 1250 (1695) @ 1200 2100 rpm
ISX12N 350 350 (261) @ 1700 1350 (1830) @ 1200 2100 rpm
ISX12N 350 350 (261) @ 1700 1450 (1966) @ 1200 2100 rpm

ISX12N Truck and Motorcoach

Overall, maintenance for the ISX12N  is similar to that of diesel engines, but there are a few key differences:

Maintenance Item^ Hours Distance Months
Oil And Filter* 500 25,000 mi (40,000 km) 6
Spark Plugs 1,000 50,000 mi (80,000 km) 12
Coolant Filter 1,500 75,000 mi (120,000 km) 12
Overhead Set Adjustment** 3,000 150,000 mi (240,000 km) 2 yrs
Cooling System Flush 6,000 300,000 mi (480,000 km) 2 yrs
Engine Brake Adjustment 6,000 300,000 mi (480,000 km) 2 yrs
Closed Crankcase Ventilation Filter 10,000 500,000 mi (800,000 km) 5 yrs
Ignition Coil Extension 10,000 500,000 mi (800,000 km) 5 yrs
Air cleaner / element Follow manufacturer's published recommendations

Consult your Owners or Operation and Maintenance manual for the complete daily and routine maintenance schedule.

^Based on a duty cycle of 50 mph / 80 kph average speed. Distance intervals may decrease based on average speed.
*Requires natural gas engine oil. These intervals apply to normal duty line haul truck and motor coach applications using CES 20085 or 20092 natural gas oil. For customers using CES 20092 natural gas engine oils only, the recommended interval is 40,000 mi (64,000 km) for vehicles with average road speeds greater than 25 mph (40 kph).
**Initial overhead set adjustment at 1,000 hours.

  • Electronic Control Module: A new engine control module, CM2380, provides full monitoring and control of the engine sensors, and the fuel and ignition systems. It offers faster processing to support heavy duty On-Board Diagnostics requirements (500K baud rate). It is also telematics capable, and provides improved diagnostics and durability.
  • On-Board Diagnostics (OBD): The OBD system continuously monitors the engine and after-treatment system. It gives the vehicle owner or repair technician electronic access to the status of various vehicle subsystems for diagnostic purposes.
  • Closed Crankcase Ventilation (CCV) system: The CCV system reduces engine emissions by capturing crankcase emissions and rerouting these gases back to the engine. This results in more complete combustion and lower emissions.
  • Enhanced Three-Way Catalyst (TWC): TWCs are effective, simple, passive devices. They provide consistent emissions control performance, are maintenance-free and can be mounted vertically or horizontally on the vehicle. No active aftertreatment such as a diesel particulate filter or selective catalytic reduction is required.

  • High-Energy Ignition System: A new Ignition Control Module (ICM) provides better performance and improved spark plug and coil durability, plus self-diagnostics.

  • Front- and Rear-Engine Power Take-Off: Options provide additional torque for a variety of vocational applications.