Cummins ISX12 Diesel Engines For Sale

Shop used Cummins ISX12 diesel engines that are inspected and run-tested before sale at HD Engines. The Cummins ISX12 is an 11.9-liter inline six-cylinder diesel engine designed for heavy-duty trucks, vocational vehicles, buses, motorcoaches, and specialty applications.

Known for strong low-speed torque, reliable performance, and a compact design compared with larger 15-liter engines, the ISX12 is used in a variety of commercial applications.

HD Engines offers Cummins ISX12 replacement engines in multiple horsepower, CPL, and emissions configurations to match different truck applications. Contact HD Engines at 786-377-5210 with your engine serial number, CPL, or truck VIN to check availability and compatibility.

Cummins ISX12 Specifications

• Manufacturer: Cummins

• Engine Model: ISX12

• Displacement: 11.9 liters

• Configuration: Inline six-cylinder diesel

• Aspiration: Turbocharged and charge-air cooled

• Fuel System: Cummins XPI high-pressure common rail

• Turbocharger: Cummins VGT variable geometry turbocharger

• Horsepower Range: Approximately 310–500 HP

• Peak Torque: Approximately 1,150–1,650 lb-ft

• Electronic Controls: CM2250 or CM2350 depending on configuration

• Applications: Heavy-duty trucks, vocational vehicles, buses, and motorcoaches
  

Specifications vary by model year, CPL, horsepower rating, emissions family, and original application. Always verify the engine serial number and CPL before ordering a replacement engine.

Cummins ISX12 Engine Features

Cummins XPI Fuel System
The Cummins XPI fuel system uses high-pressure common-rail injection technology to provide precise fuel delivery and efficient combustion.

Variable Geometry Turbocharger
The VGT turbocharger adjusts airflow based on engine conditions to support responsive performance and engine braking.

Electronic Controls
The ECM manages fuel delivery, turbocharger operation, engine protection systems, and emissions functions. ISX12 engines may use CM2250 or CM2350 control systems.

Compact Heavy-Duty Performance
The ISX12 provides strong horsepower and torque in a smaller package compared with larger displacement engines, making it suitable for regional hauling and vocational applications.

Cummins ISX12 Horsepower and Torque Ratings

Cummins ISX12 engines are available in multiple horsepower and torque configurations depending on the model year, CPL, calibration, and vehicle application.

Common ratings include:
310 HP – up to approximately 1,150 lb-ft torque
330 HP – approximately 1,250–1,350 lb-ft torque
350 HP – approximately 1,350 lb-ft torque
370 HP – approximately 1,350–1,450 lb-ft torque
385 HP – approximately 1,450 lb-ft torque
400 HP and higher-output versions – up to approximately 1,650 lb-ft torque

Confirm the engine data plate, serial number, and CPL to identify the correct factory configuration.

Common Cummins ISX12 Applications

The Cummins ISX12 is commonly used in:

• Regional-haul trucks

• Day-cab trucks

• Dump trucks

• Refuse trucks

• Concrete mixers

• Crane trucks

• Tanker trucks

• Delivery trucks

• Emergency vehicles

• Motorcoaches

• Transit buses

• Recreational vehicles

Cummins ISX12 CM2250 vs CM2350

The Cummins ISX12 CM2250 and CM2350 versions use different electronic systems and emissions configurations.

CM2250 engines are commonly found in earlier EPA-era applications and use XPI fuel injection, VGT turbocharging, and integrated emissions controls.

CM2350 engines feature updated electronics, sensors, calibrations, and emissions components. These engines should not be considered automatically interchangeable because ECMs, wiring harnesses, sensors, turbocharger controls, and aftertreatment systems may differ.

ISX11.9 vs ISX12

ISX11.9 and ISX12 are commonly used names for the same 11.9-liter Cummins engine platform. Some engine listings and service documentation may use ISX11.9, while later marketing materials use ISX12.

Identifying the Correct Cummins ISX12 Engine

Before purchasing a Cummins ISX12 replacement engine, provide:

• Engine serial number

• CPL number

• Engine model

• Horsepower rating

• ECM type

• Emissions family

• Truck model year

• Vehicle identification number (VIN)

The engine serial number and CPL help verify the original configuration. Two ISX12 engines may look similar but have differences in internal components, electronics, sensors, oil pans, and emissions equipment.

Used Cummins ISX12 Engines: Inspection and Testing Process 

Available Cummins ISX12 engines are inspected and may be run-tested before sale depending on the individual listing.

Depending on the engine, inspection may include:

• Engine startup and operation

• Oil pressure verification

• Blow-by observation

• Oil and coolant inspection

• Fault-code inspection

• External leak inspection

• Turbocharger operation

• Mechanical condition review
  
  Testing procedures, included components, and warranty coverage vary by engine. Review the individual listing or contact HD Engines for specific details.

What Is Included With an ISX12 Engine?

Included components vary by engine listing. A complete engine may include:

• Cylinder block and crankshaft

• Cylinder head

• Fuel injectors

• High-pressure fuel pump

• VGT turbocharger

• Intake and exhaust manifolds

• Oil cooler

• Air compressor

• Starter and alternator

• ECM and wiring harness

          Always confirm included components before purchase.

Why Choose HD Engines for a Cummins ISX12 Replacement Engine?

HD Engines helps customers find compatible Cummins ISX12 replacement engines by verifying engine serial numbers, CPL information, and application details. Available engines are inspected before sale, and our team can help identify suitable replacement options for different truck and vocational applications.

With experience supplying commercial diesel engines, HD Engines focuses on helping customers match the correct engine configuration before purchase. Contact our team with your engine serial number, CPL, or VIN to check availability.

Nationwide Cummins ISX12 Engine Shipping

HD Engines can arrange commercial freight shipping for Cummins ISX12 engines throughout the continental United States. Engines are prepared for transportation using appropriate freight handling methods.

Commercial delivery locations with forklift or loading dock access are recommended. Freight-terminal pickup may also be available.

Find a Cummins ISX12 Engine for Sale

Need a Cummins ISX12 replacement engine? Contact HD Engines with your engine serial number, CPL, and truck VIN. Our team can help compare available inventory and identify suitable replacement options.

Call HD Engines at 786-377-5210 for Cummins ISX12 availability, pricing, and shipping information.