5.9L Cummins ISB (24 Valve)

5.9L Cummins 24v Specs, History, & Information

The acronym "ISB" stands for Interact System, B Series. It represents the fact that the engine uses an electronically controlled injection system, and is part of Cummins "B Series" engine family. All 24v Cummins were assembled at the company's Columbus, Indiana assembly plant, the same city in which the "Cummins Engine Company" was founded. For 2004, the engine was selected as one of Ward's "10 Best Engines" for the year. Production of the 5.9L ISB ended completely (all applications) in June of 2009.

High Output 24v Cummins

A high output (H.O. or HO) version of the 5.9L Cummins was available for the 2001 to 2004 model years. For 2001 and 2002, the HO Cummins boasted an additional 10 horsepower and 45 lb-ft of torque. In 2003, the HO model produced a whopping 70 horsepower and 95 lb-ft more than the standard turbodiesel. And for 2004, the optional high output engine claimed 20 horsepower and 45 lb-ft of torque greater than the standard model. The HO Cummins was not available in California, which has historically been a state with stricter emissions regulations than those imposed at the Federal level. The NV5600 6 speed manual transmission was the only transmission available mated to HO models of the Cummins, as at the time the available automatic was not rated with an adequate input capacity. High output models featured higher compression and a unique engine calibration to provide the additional performance.

5.9L Cummins ISB Specs

Engine	Cummins 5.9L ISB (commonly referred to as the "24 valve")
Manufacturer	Cummins Engine Company, later Cummins Inc
Applications/Production Years	1998.5 - 2007 Dodge Ram 2500/3500 pickups Various industrial, agricultural, and motorhome applications of similar period
Displacement	359.02 CID (359 CID nominal), 5.88 liters (5.9 liters nominal)
Configuration	Inline 6 cylinder (I-6), 4 cycle diesel
B10 Life	Note rated
B50 Life	350,000 miles (~560,000 km)
Bore	4.02 inches (102 mm)
Stroke	4.72 inches (120 mm)
Bore/Stroke Ratio	0.85 (undersquare)
Compression Ratio	Standard models	16.3 : 1
	High output models	17.2 : 1
Firing Order	1 -5-3-6-2-4
Cylinder Numbers
Engine Block Material	Cast iron
Cylinder Head Material	Cast iron
Injection System	Direct injection (DI)
	1998.5 - 2002	Electronically controlled Bosch VP44 rotary injection pump
	2003 - 2007	Bosch high pressure common rail, Bosch CP3 injection pump
Aspiration	Turbocharged, air-to-air intercooler
	1998.5 - 1999	Holset model HX35W turbocharger
	2000 - 2004	Holset model HY35W type D turbocharger
	2004.5 - 2007	Holset model HE351CW turbocharger
Valvetrain	OHV, 4 valves per cylinder, solid lifter camshaft
Valve Lash (Clearance)	Exhaust valves	0.020 inch (engine cold)
	Intake valves	0.010 inch (engine cold)
Cold Start Aid(s)	Intake air grid heater mounted between air horn and intake manifold
Engine Oil Capacity	12 qts w/ filter change
Engine Oil Spec	See 24v Cummins maintenance schedule for engine oil viscosity chart
Fuel	#1/#2 diesel fuel; engine predates modern biodiesel availability[1]
Horsepower	235 - 325 hp @ 2,900 rpm
Torque	460 - 610 lb-ft @ 1,600 rpm
Governed Speed	3,200 rpm
Engine Weight	~ 1,150 lbs, dry & dressed
Engine Dimensions	Length	40.0 inches
	Width	24.9 inches
	Height	37.9 inches

^[1] Early 5.9L ISB engines predate modern ULSD regulations and biodiesel compatibility. The engine will run without issue on both fuels, although the effects of extended biodiesel usage are largely sporadic, vague, and/or unknown. Recommend a supplemental fuel additive to increase fuel lubricity regardless of diesel type used, which will prolong fuel system life.

24v Cummins Horsepower & Torque by Model Year

Note - The following ratings are only applicable to Dodge pickups.