4BT Cummins

3.9L Cummins 4BT Specs, History, & Information

The Cummins 4BT is essentially a 5.9L 12v Cummins minus two cylinders. This 3.9L, 4 cylinder, inline diesel was commonly used in commercial van applications (popular application for Chevy Step Vans – think bread delivery trucks), as well as a variety of construction and agricultural equipment. Generous amounts of torque in a small package make the 4bt common for engine swaps in Jeeps & small trucks/SUVs.

The 4BT is dimensionally similar to the 6BT, save for a much shorter length. The pistons, injectors, connecting rods, and valvetrain design are straight off of the 12v Cummins. Because inline 4 cylinders are not inherently balanced like inline 6 cylinder engines, the engine is noticeably harsher than its larger brother. The engines can be found in applications with up to a 16,000 lb GVWR, which should serve as a limit for anyone whom plans to use the engine in a custom application.


4BT Cummins Specs

Configuration: Inline 4 cylinder
Displacement: 3.9 liters, 239 cubic inches
Bore x Stroke: 4.02″ x 4.72″
Cylinder Head Material: Cast iron
Engine Block Material: Cast iron
Firing Order: 1-3-4-2
Compression Ratio: 17.5 : 1
Injection: Direct injection, mechanical injection pump
Aspiration: Turbocharged, non-intercooled
Valvetrain: OHV, 2 valves per cylinder
Weight: 745 – 782 lbs w/ oil
Oil Capacity: 10 quarts
Governed Speed: Varies with application
Horsepower: 105 hp @ 2,300 rpm *
Torque: 265 lb-ft @ 1,600 rpm *

* Common rating, output may vary considerably with application.


Diesel Nation currently has 4BT diesel engines in stock and ready to ship. We have new, complete diesel engines. Give us a call today or fill out the form below to get your no obligation quote!


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