7.2 Cummins B-Series

The 7.2 liter Cummins B7.2 is a new B-Series engine under development for medium duty vehicle applications with availability scheduled for the 2027 model year. There are various claims that the 7.2 liter will replace the 6.7 turbodiesel in Ram pickup and chassis cab models - these are entirely unsubstantiated and, at this juncture, seemingly unlikely considering the substantial investment put into the 2025 model year 6.7 Cummins update.

The B7.2 shares the same 4.21 inch cylinder bore as the 6.7 liter but utilizes a longer 5.24 inch stroke length to the 6.7's 4.88 inch stroke, resulting in the larger displacement. Although comprehensive and finalized details have not yet been revealed the 7.2 liter engine is not, by design, an evolution of the 6.7 ISB. For example, the 7.2 Cummins utilizes a dual overhead camshaft design whereas the 6.7 is an overhead valve engine. This feature alone substantially changes the structure of the engine block and cylinder head.

Enhanced Aftertreatment System

It is no coincidence that the B7.2 is scheduled for 2027 as this target is aligned with more stringent EPA and CARB emissions regulations set to go into affect for 2027 model year vehicles. The updated rules are fairly comprehensive in that they require reductions in several categories of pollutants, including greenhouse gases, nitrogen oxides, particulate matter, hydrocarbons, and carbon monoxide.

It is likely that these requirements serve as the primary driving force behind the development of this new engine. The 7.2 Cummins will feature an even more sophisticated exhaust aftertreatment system to meet the upcoming emissions mandate. In addition to automatic engine shutdown and start-stop features, expect to see electrically heated catalysts and enhanced sensory guidance in the SCR and particulate filter systems. It is currently unknown what additional equipment and cold-start aids Cummins will utilize on the engine platform.

Power Ratings

Like other commercial engines of its kind, the 7.2 liter will be offered in a variety of horsepower and torque ratings tailored to industry specific requirements. The official word from Cummins is that peak output will range between 240 and 340 horsepower and 650 to 1,000 lb-ft of torque. The table below summarizes the range of horsepower and torque combinations advertised by Cummins at the time of publishing.

Engine Specifications

Production Years	Scheduled for 2027 introduction
Assembly Plant	Cummins Rocky Mountain Engine Plant, Whitakers, North Carolina
Applications	Medium duty trucks, vocational, Ram pickup & chassis cab trucks
Type	Direct injection 4 stroke turbodiesel
Configuration	Inline 6 cylinder
Displacement (advertised)	7.2 liters
Calculated Displacement	7.17 liters, 437.64 cubic inches
Bore	4.21 inches (107.0 mm)
Stroke	5.24 inches (133.0 mm)
Bore/Stroke Ratio	0.80 (undersquare)
Firing Order	1-5-3-6-2-4
Cylinder Numbers
Compression Ratio	TBA
Engine Block Material	TBA
Cylinder Head Material	TBA
Valvetrain	Dual overhead camshafts (DOHC), 4 valves per cylinder, compression release engine brake ("Jake brake" [1])
Reciprocating Assembly	TBA
Rotating Assembly	TBA
Aspiration	Turbocharged, Holset turbocharger
Starting Aids	TBA
Injection Pump	TBA
Engine Oil Capacity	TBA [2]
Governed Engine Speed	2,400 rpm
Horsepower	240 - 340 horsepower
Torque	650 - 1,000 lb-ft
Dry Engine Weight	1,359 lbs

[1] - "Jake brake" refers to a specific line of compression release engine brakes developed and manufactured by Jacobs Vehicle Systems, which Cummins fully acquired in 2022. It is a type of engine retarder that releases cylinder pressure at the top of the compression stroke to minimize the rebound effect of the compressed air charge during the following stroke, increasing the braking effort of the engine.
[2] - A large engine oil capacity is anticipated to corroborate extended oil drain intervals advertised by Cummins