Specifications
The 4BT Cummins engine is a 3.9-liter, 4-cylinder turbo-diesel engine known for being very simple, tough, and long-lasting. It was first used in industrial machines and delivery trucks, but it became popular for custom truck and off-road builds because it’s compact, easy to work on, and extremely reliable —many engines last close to a million miles. It has a strong cast-iron block, a mechanical fuel pump, and gear-driven parts, which make it durable and easy to maintain. Depending on the model, the 4BT usually makes 105–170 horsepower and 265–420 lb-ft of torque, and with upgrades, it can make even more. These features make the 4BT a favourite engine for swaps and tough working vehicles.
A 4BT Cummins offers strong pulling power, long life, and good fuel efficiency, making it great for project trucks, off-road rigs, and custom conversions. Our tested used and rebuilt 4BT engines go through full inspections, compression and leak-down testing, fuel-pump calibration, and turbo checks to ensure smooth starting, proper fuel delivery, and good boost.
Engine Variant
4BT Cummins Engine
The 4BT Cummins engine remains one of the most celebrated small-displacement diesel engines in modern mechanical history. Originally engineered for commercial trucks, generators, and heavy-duty equipment, the 4BT is built for endurance under severe conditions. Every component from its forged-steel crankshaft to its high-pressure mechanical injection pump to its gear-driven camshaft is designed to deliver dependable, high-torque output with minimal maintenance. More than just an engine, the 4BT represents the essence of diesel reliability: efficient, powerful, easy to service, and capable of operating well beyond 300,000 miles with basic care.
4BT (3.9L)
The standard 3.9-liter Cummins 4BT has a 102 mm (4.02 in) bore and a 120 mm (4.72 in) stroke, which gives it strong low-end torque. It uses a heavy-duty cast-iron block and head, along with a basic but reliable direct-injection fuel system. The engine usually runs a mechanical VE or P-pump, both known for being easy to tune and very durable. Depending on where it’s used, the 4BT can come with different turbochargers, an intercooler, and various accessory setups, making it easy to fit into many types of builds.
4BTA (Intercooled Turbo) Variant
The 4BTA is an upgraded, intercooled version of the 4BT is built to make more power and efficiency. It uses an air-to-air intercooler, a higher-flow turbo, and improved fuel delivery, which together give it a stronger mid-range power and better fuel economy. The 4BTA makes about 150–170 hp and 350–420 lb-ft of torque, making it popular for heavy-duty work and performance builds. With its mix of power, efficiency, and proven reliability, the 4BTA stands as a top choice for diesel fans who want a stronger version of the 4BT.
Frequently Asked Questions
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Is this 4BT Cummins engine new or used?
All engines are tested used condition, ensuring reliability and OEM fitment.
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Will it fit my truck or van?
The 4BT Cummins engine fits a variety of OEM vehicle; check year and model compatibility for exact fitment.
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What is the horsepower and torque range?
Depending on year and variant, 4BT engines produce 105–160 hp and 265–400 lb-ft of torque.
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Does it come with a warranty?
Yes, all engines include a limited warranty for peace of mind.
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Is it suitable for industrial or marine use?
Absolutely—its robust design supports trucks, industrial machines, and marine applications.
4BT Cummins Engine
