Cummins ISM Engine
Power
280-450 HP
Torque
1150-1550 LB-FT
The Cummins ISM is one of the most trusted mid-range heavy-duty diesel engines ever produced by Cummins, known for its reliability, strong torque curve, and excellent fuel economy. Introduced in the late 1990s as the successor to the M11, the ISM carried the proven mechanical foundation of its predecessor while introducing modern electronic controls, improved combustion technology, and better emissions performance.
Throughout the 2000s, the ISM became a popular powerplant for Class 8 trucks, vocational applications (dump trucks, mixers, refuse trucks), and buses. Available from 280 HP up to 450 HP, the ISM offered fleets and owner-operators a lightweight yet capable engine that delivered impressive pulling power without sacrificing fuel efficiency.
The ISM remained in production until it was eventually replaced by the Cummins ISX11.9 / ISL9 platform as emissions standards advanced. Today, the ISM is still widely used and appreciated for its durability, ease of service, and strong aftermarket parts support—making it a top choice for rebuilders, truck operators, and equipment owners.
Cummins ISM Engine Specifications
| Category | Details |
|---|---|
| Engine Model | Cummins ISM (formerly M11) |
| Displacement | 10.8L (661 cubic inches) |
| Configuration | Inline 6-cylinder, 4-stroke diesel |
| Bore x Stroke | 4.92 in x 5.79 in (125 mm x 147 mm) |
| Compression Ratio | 16.3:1 (varies by calibration) |
| Horsepower Range | 280 – 450 HP |
| Torque Range | 1050 – 1550 lb-ft |
| Fuel System | High-pressure fuel injection (HPI) or CM870/CM875 electronic control |
| Aspiration | Turbocharged & Aftercooled |
| Governed Speed | 2000 – 2100 RPM |
| Emissions | Pre-EPA04, EPA04, and EPA07 variants |
| Weight (Dry) | Approx. 2,000 lbs |
| Applications | Class 8 trucks, vocational trucks, buses, construction equipment |
